Studies reporting the potential to support the adaptation characteristics and muscle function recovery of human muscle structures following the intake of CitMal supplements remain limited 123,134. Another previous study found that 8 g of CitMal taken 2 h before exercise had no effect on peak torque, average torque, total work, or metabolic efficiency, blood flow, or lactic acid clearance during five sets of concentric leg extensions . Some previous studies have failed to find a positive effect of CitMal supplementation on isokinetic or dynamic muscular power indices 56,133,135,138. Similar results were observed in a study of resistance-trained females, with improved performance responses during six sets of plate-loaded leg press and bench press exercises at 80% 1RM . This has been evidenced by the results of numerous studies performed on in vitro and in vivo models, as well as some clinical trials involving patients with carbohydrate and lipid metabolism disorders.Nitric oxide is a signaling molecule that regulates blood vessel dilation, improving circulation and oxygen delivery to various tissues, including the testes.Several amino acids, particularly arginine, glutamine, leucine and phenylalanine directly stimulate the production of insulin from pancreatic beta cells16.Effects of L-arginine in the treatment of carbohydrate metabolism disorders.It is possible that this phenomenon may be related primarily to the adaptation to high hypoxic loads and the functioning of the NO system under intensive training.The adverse effect rate in the arginine-treated group was 8.3%, and that in the placebo group was 2.3%, none of which were severe.L-arginine administered to healthy rats, did not significantly affect any of the parameters . Guidelines for Reviewers The main role of arginine in the human body is to be a substrate for the synthesis of nitric oxide (NO), as shown earlier by Zembowicz .Out of them, in 8 studies the protocol consisted of 6 g/day of Arg 31,32,40,41,58,59,62,63, in 2 trials 2 g/day was used 9,57, in 1 study 12 g/day was ingested , another one provided 3.7 g , Abel et al. used 5.7 g/day and 2.85 g/day for each group and the remaining one provided 1.5 g/d and 3 g/day .L-arginine can be produced in the body as a result of the conversion of L-citrulline, and in the liver, L-arginine is metabolized into L-citrulline.At the same time, shocks of different origins are characterised by hyperproduction of NO, which leads to impaired vasoconstrictor responses 28,29,67.To best of our knowledge, no study has evaluated the effects of 2g of L-arginine per day on cardiovascular risk factors.This article delves into the various aspects of L-arginine, including its effectiveness, dosage, and benefits, particularly in the context of sexual health and erectile dysfunction (ED).Related mechanisms include reduced oxidative stress, increased antioxidant capacity, inhibited inflammation and apoptosis, restored the secretory activity of the HPT axis, reduced chromosomal variation, enhanced sperm mitochondrial energy metabolism, cell membrane stabilization effect, etc.Ghanbarzadeh S, Garjani A, Ziaee M, Khorrami A. Effects of l-carnitine and coenzyme q10 on impaired spermatogenesis caused by isoproterenol in male rats.Interestingly, lifetime exposure to flavonoids such as daidzein (5) and genistein (6) increased serum and testicular testosterone levels in rats . Jabłecka et al. (2012) conducted a study on individuals with atherosclerotic peripheral arterial disease of lower extremities at Fontaine’s stage II and coexisting T2DM. In contrast, it did not affect, among others, total cholesterol (T-C), TG, glucose and TNF-α levels . Supplementation caused a significant decrease in Homeostatic Model Assessment–Insulin Resistance (HOMA-IR) and insulin levels. Effects of D-aspartate on the synthesis of LH and cGMP in the isolated rat pituitary Another study, conducted by Ortiz et al. (2013), investigated the physiology of mitochondria and their production of NO in cortex cells of rats with induced diabetes and the effect of L-arginine administration on these cells.On PubMed, 24.8% of supplements had data showing an increase in T with supplementation, 10.1% had data showing a decrease in T, and 18.3% had data showing no change in T.Within seminiferous tubules, appropriate Sertoli cell function is highly dependent on testicular androgen levels and is essential to initiate and maintain spermatogenesis.So L-arginine supplements help supply the much-needed building blocks for the development of the muscles of your body.By converting arginine into L-citrulline, an additional amino acid, nitric oxide synthases, also known as NO synthases, produce NO as a byproduct.The research is less clear on how L-arginine should be spaced out throughout the day. The literature was examined regarding the effects of Arg supplementation on sports performance using athletic performance outcome variables classified according to the duration of tests used. However, to the best of the authors’ knowledge, there is not clearly and quantitatively analyzed information and distinction regarding the different involved effects in both aerobic and anaerobic performance capacities in the literature, and this may be necessary to better understand Arg supplementation reasons and protocols. Although Arg supplementation could be effective on aerobic and high-intensity sport disciplines performance mediated by several effects, current evidence is controversial and confusing. These positive effects related with strength could be explained because of Arg enhance GH-releasing hormone, suppresses the endogenous GH-inhibiting hormone and increases insulin-like growth factor 1 (IGF-1) 37,38. Moreover, Arg supplementation has presented a reduction of ammonia, lactate, fatty acids, and fat oxidation levels after exercise 23,24. As a result, the circulating testosterone levels decrease because of the suppression of androgen synthesis and induction of apoptosis in the Leydig cells. ROS directly inhibit the male reproductive function by increasing the effect of glucocorticoids on Leydig cells. Many studies have reported that ROS disrupt sperm parameters in men with idiopathic infertility. After researching and talking with some best physicians, we found “Testonine” that can naturally boost your testosterone level. So, how can you find the best L-Arginine supplement with no side effects? Many L-Arginine supplements are on the market, and not all are good for you. Many physicians suggest fitness freaks and gym-goers take sufficient doses of L-Arginine supplements. The erectile domain of IIEF scores increased from 15 to 25 after 3 months and to 27 after 6 months, whereas placebo enhanced scores from 15 to 19.1 and 19 after 3 and 6 months. L-citrulline was added because it increases plasma L-arginine concentrations more effectively than L-arginine itself . Following 8 weeks of supplementation, the total IIEF score increased, but did not reach stat. Due to their neurotrophic activities, their integrative use has been studied in several different physio-pathological conditions such as anorexia nervosa, chronic fatigue, vascular diseases, Alzheimer’s disease and male infertility. Although product recommendations are only our opinions, this research-backed page has been fact-checked and reviewed by a certified nutritionalist or health specialist. Alternatively, you can try stimulating nitric oxide production through a different pathway entirely. A good example of another compound related to the same nitric oxide production pathway is citrulline. The higher end of the dosage range is typically reserved for clinical trials on people with heart disease or hypertension, while studies on sports and athletes in training use more middle-of-the-road doses, around five grams per day. We discuss the synthesis of L-arginine and its transporters, which affect the physiology of endothelial vasodilation. We conducted a narrative review of the literature about L-arginine with a special focus on articles that discuss its physiology, its effect on the kidney, and its administrating routes. In the search of finding an urgent treatment for this chronic disease, researchers discovered that the vascular endothelium is a vital factor affecting blood pressure. In the present review, the role of L-arginine, arginine transporters, and ADMA in the pathobiology of HTN and their potential clinical significance are discussed. Production of adequate amounts of NO by vascular endothelial cells is essential to maintain normal blood pressure and prevent the development of HTN. You might find yourself becoming anaemic, with low red blood cell counts, and you may experience fertility issues. However, plenty more have suboptimal levels – they could improve their naturally occurring levels, benefitting greatly as they do so. Men’s levels peak in early adulthood, so around the early to mid twenties. HisHealthMag is the ultimate online destination for accurate, current information about men’s health, fitness, and overall well-being. L-Arginine alleviates the testosterone reduction in heat-treated mice by upregulating LH secretion, the testicular antioxidant system and expression of steroidogenesis-related genes While ALC appears to be the preferable choice to use for Alzheimer’s disease and other brain disorders, propionyl-L-carnitine (PLC) seems to be the most effective for chest pain, ischemic heart disease, congestive heart failure, hypertrophic heart disease and peripheral vascular disease . Additionally, L-carnitine is important in maintaining cell membrane stability through its involvement in acetylation of membrane phospholipids and amphiphilic actions 10,11. In conclusion, carnitine modulates the intramitochondrial acetyl CoA/CoA ratio as it regulates the supply of acetyl-CoA from both the PDH complex and from β-oxidation of fatty acids. Study Overview from PubMed Therefore, a more effective treatment for ED is required. These methods are often not acceptable to patients because they are invasive, complex, and expensive (16). This rapid blood inflow leads to compression of the venous network and reduction of venous outflow, thereby increasing the intracavernous pressure of the penis and leading to erection (11, 12). NO is the messenger cell of penile erection, which is produced by neuronal NO synthase (NOS) of penile non-adrenergic, non-cholinergic nerve terminals and endothelial NOS (E-NOS) of penile artery endothelial cells. When the body experiences sexual stimulation, paraspathetic nerve activity from the sacral part of the spinal cord triggers a series of reactions, releasing nitric oxide (NO) and increasing the intracellular cyclic guanosine monophosphate (cGMP). These studies provide valuable insights into the protective effects of L-Carnitine in mitigating the adverse effects of copper toxicity and chemotherapy-induced damage on testicular function and sperm quality.As previously reported , age-related decline in testosterone production may be delayed by increasing StAR and/or Cyp11a1 gene expressions using supplementation with flavonoids or chemical derivatives.Embrace a healthier lifestyle and enjoy the benefits of improved hormone balance.As you can see, l-arginine has some very definite benefits.For the energy related parameters, at D10, there were no significant changes in the glucose levels (mg/dl) and cholesterol levels (mg/dl) between L-arginine treated and Control group.This study was conducted at the Animal Production Farm of Faculty of Agriculture, Al-Azaher University (Assuit branch) which is located at 70 m above mean sea level, latitude 27.18° N, and longitude 31.19° E.E-NOS activity is inhibited by the asymmetric dimethylarginine (ADMA) which acts as a strong competitive inhibitor for the formation of NO from L-arginine . Reproduction, Fertility, and Development. Could zinc prevent reproductive alterations caused by cigarette smoke in male rats? Advancement of puberty and enhance-ment of seminal characteristics by supplementation of trace minerals to bucks. Reproduction, Nutrition, Development. The same group of researchers (Bahadoran et al., 2017) investigated the association of dietary L-arginine intake and the risk of chronic kidney disease in 1780 adults (men and women). It was found that higher intake of plant derived L-arginine may have a protective effect whereas animal-derived L-arginine may be a risk factor for development of hypertension and CHD events . The lower dose (3 g, 3 times daily) resulted in a decrease in body weight, blood pressure, T-C, LDL-C level and malondialdehyde (MDA) concentration compared to the results of this group before supplementation. A decrease in growth hormone secretion is observed with aging, which may result in an increased risk of these diseases. A healthy diet and regular exercise are among the best ways to keep your blood pressure healthy. Also, don't take L-arginine if you have kidney disease. Too much L-arginine in your system can make the virus that causes those conditions become active again. Don't take L-arginine if you've had a heart attack. Arginine significantly increased serum IGF-1 levels and improved nitrogen balance, compared to the control group. Patients took 30 g arginine aspartate (17 g free arginine) or placebo dissolved in syrup, for 2 weeks. Administration of L-arginine or L-citrulline reversed the increase in serum AST and ALT activities, urea concentration and lipid profile parameters. L-citrulline is also important in the production of NO, so it is worth comparing its action with L-arginine. The researchers suggest that the beneficial effect of L-arginine administration on serum glucose values and lipid levels in diabetic rats may be due to the polyamine formation . These findings highlight the role of L-Carnitine in enhancing seminal antioxidant activity, preventing MDA production, and protecting spermatozoa during storage in the epididymis and oviduct in aged roosters.Plasma L-arginine, NOx and c-GMP levels increased in both the biscuits and supplement cases.L-arginine’s ability to improve blood flow may also help improve athletic performance.In GH3 cells, GH mRNA expression levels significantly increased 2.11 and 4.88 fold when using 10 and 25 mM l-arginine compared with those of the control, respectively (Fig. 1A).Through its ability to be converted into nitric oxide, L-arginine plays a vasodilator role that improves blood flow and increases oxygen and nutrient flow to the muscles, improving endurance and muscle recovery.Yes, physically active individuals may experience greater benefits from L-arginine supplementation in terms of testosterone support.The modifications that L-arginine supplementation causes in muscle growth and testosterone levels may be helpful in elucidating the physiological processes underlying its purported advantages for strength and endurance.The applied dose of testofen in the present study was 600 mg/d. Other potential off-label prescription treatment options for HSDD and related conditions include bupropion, androgen therapy, sildenafil citrate, bremelanotide, and ospemifene. The use of flibanserin is restricted to a Risk Evaluation and Mitigation Strategy (REMS) program in order to increase awareness of the high risk of syncope and severe hypotension that occurs when taken with alcohol . The most common adverse effects include dizziness, somnolence, nausea, and fatigue, which may be mitigated via nighttime dosing. Explore Our Best Heart Health Supplements In male reproductive organs, taurine has been detected by immunohistochemistry in Leydig cells of the testis, vascular endothelial cells, and other Leydig cells, as well as epithelial cells of the efferent ducts (26). Here, we review the role of taurine in maintaining physiological function of the male reproductive system, inhibiting pathological developments and alleviating toxic damage, hoping it provides ideas for future research. Additionally, further studies have found that taurine has protective effects on reproductive toxicity induced by heavy metals or some drugs (13, 18). The results of the current randomized, double-blind, placebo-controlled clinical trial demonstrated that oral administration of l-ARG at the dose of 6 g/day for 3 months significantly improved penile erectile function assessed by IIEF-6 score and PSV evaluated at dynamic PDU in 50 male patients with vasculogenic ED, compared to 45 placebo-treated patients. Evaluation of penile erectile function, and prevalence of mild, mild–moderate and moderate ED assessed by IIEF-6 questionnairea, and prevalence of mild–moderate and severe vasculogenic ED assessed at dynamic PDUb, at baseline (T0) and after 90 days (T1), in l-arginine and placebo groups, in the overall cohort At study entry, patients were allocated to l-ARG or placebo group using standard randomization tables; patients and clinicians were blinded regarding the treatment modality. The present study showed that GH levels increased more with ARG + GHRH than with ARG or GHRH alone. The participants trained 4 times/week while orally ingesting either 3 gr of placebo or D-Asp in the morning upon waking. It seems the allocation of participants to the study groups was not random. In addition, except the age, no details of the participants were reported (e.g. weight, physical activity). Inclusion and exclusion criteria were not specified and it is a methodological limitation for this study. Other studies showed that D-Asp directly inhances aromatase activity (5, 6, 31, 36, 42, 43, 47). One study (25), which could not be combined with other studies because of the use of the IIEF-5 and salivary T assessment, showed an improvement in total IIEF-5 scores compared with placebo after 8 weeks of PAL intake. In summary, PAL may be safe and effective in improving sexual function in patients with mild to moderate ED. The main observation indicators of this study were IIEF scores (erectile domain), whereas the secondary observation indicators were overall satisfaction scores, intercourse satisfaction scores, sexual desire scores, orgasmic function scores and T. This study compared the efficacy and safety of daily concomitant administration of PAL or oral placebo in patients with ED. Among all the included clinical trials, sexual desire was reported in two studies (24, 26). The limitations of the current study included the assessment of erectile dysfunction by IIEF-6 rather than IIEF-15 questionnaire, with a consequent potential underestimation of additional domains of sexual function which might have been positively influenced by l-ARG supplementation. In particular, an RCT including 108 diabetic patients with mild–moderate ED demonstrated that a daily treatment with 5 g l-ARG plus 10 mg tadalafil, administered for 8 weeks, significantly improved ED assessed by IIEF-5 and testosterone levels, with a more significant improvement in both endpoints compared to patients receiving tadalafil or l-ARG as single compounds, whereas the significant improvements at basal and dynamic PDU were similar between groups . Consistently, in the current study, only 5.88% of patients in l-ARG group experienced adverse effects (including gastric pyrosis, urticarial reaction and scrotal itching), but none of which was manifested as clinically relevant, and did not induce treatment discontinuation. What’s the Relationship Between L-Arginine and Physical Activity? Nitric oxide (NO) may also affect sexual function by mediating vascular smooth muscle relaxation. Individual-specific factors also affect female human sexual desire such as intimacy, pleasure, partnership issues, sexual knowledge, and the wish to participate or behave in a sexual fashion. DSM V, combined HSDD and FSAD into the definition of female sexual interest/arousal disorder (FSIAD) . Additionally, female sexual arousal disorder (FSAD) was defined as persistent or recurrent inability to achieve and maintain adequate lubrication-swelling response of sexual excitement until completion of sexual activity. More trials with a specific type of patients would help further understand and explore the effects even more. L-arginine transport can be affected by the extracellular concentration of cationic and neutral amino acids . Cellular L-arginine transport can be affected by extracellular concentration of L-arginine, cationic or neutral amino acids . There are two main transport systems, y+ and y+L, which are responsible for transporting L-arginine and cationic and neutral amino acids through the plasma membrane. The same effects occurred also when the concentration of D-Asp in the medium was 1.0 mM.Contrastingly, a study of male soccer players who consumed 2 g of Arg supplements per kg of body weight for 45 days reported an improvement in maximum oxygen consumption .The study was conducted among adults above 60 years of age to find out if the daily supplementation of Arg affects ED.Now you know, that L-arginine and zinc benefits you in many ways.Also, Zinc and L-Arginine are important for many body functions.Thus, each participant served as their own control, reducing the need for a large number of participants by minimizing the influence of confounding variables.The production of L-Arginine decreases due to some health conditions or in older adults. In addition, unpublished gray literature and references cited in eligible studies were retrieved. It is expected to provide more reliable evidence for the efficacy and safety of the combination of PAL in patients with ED. Pycnogenol is a very strong antioxidant (19), which increases NO synthesis by catalyzing E-NOS (19, 20). Importantly, plasma concentrations of flavonoids for an adequate response of testicular Leydig cells are in the low micromolar range which can be attained with high quality nutrition mainly composed of fruits and vegetables. In addition, this anthocyanin also upregulated the activities of the MAPK and PKA signalling pathways , promoting steroid production. In this study, they found that EGCG (19) inhibited the PKA/PKC signalling pathways and decreased the enzyme activity of Cyp11a1 and Hsd17b3. Therefore, flavanones may have the potential to prevent testosterone decline in response to endocrine disruptors, and possibly to aging. Subjects had blood and urine samples collected, were asked about their general health condition and examined by a physician before the start of the study, and again at 8 and 16 weeks after the study. The study was designed as an open, randomized, two-arm study comparing the commercialized food supplement Nokogiriyashi EX® (manufactured by Kobayashi Pharmaceutical Co., Ltd., and containing 160 mg SP extract per tablet) and Edicare® (manufactured by Kobayashi Pharmaceutical Co., Ltd., and containing 10 mg of Pycnogenol®, 115 mg of l-arginine, and 92 mg of aspartic acid per tablet). The inclusion criteria were 1) male patients between 55–80 years of age; 2) an International Prostate Symptom Score (IPSS) of 8 or more; 3) the presence of LUTS for at least 2 months; and 4) the presence of SDys (erectile dysfunction and/or decreased libido). Does L-Arginine Really Boost Up Testosterone Level in the Body?? While, Serum testosterone level was measured using ELISA kits (Bio Check, Foster City, CA 94404, USA). Collecting tubes coated with sodium fluoride were used for determination of glucose levels. And the total number of spermatozoa per ejaculate was calculated by multiplying the ejaculate volume × concentration per ml. However, results comparing PAA to SP group in this study demonstrated that change from baseline of IIEF5 was significantly improved in the PAA group. The results of this study showed that consumption of a supplement of SP significantly improved IPSS total, subscore of storage and voiding, IPSS-QOL. Patients were in their fifties compared to the mean age of 76.1 years in the present study.13 L-arginine protects against t-2 toxin-induced male reproductive impairments in mice. Resistance training and l-arginine supplementation are determinant in genomic stability, cardiac contractility and muscle mass development in rats. Oi Y, Imafuku M, Shishido C, Kominato Y, Nishimura S, Iwai K. Garlic supplementation increases testicular testosterone and decreases plasma corticosterone in rats fed a high protein diet. Naringenin (14, Figure 7), a flavanone found in grapefruits, has been reported to inhibit the activity of Hsd17b3 and Hsd3b in male rats after daily subcutaneous injections of 15 mg/kg . Overall, flavonols such as quercetin (7) are promising in increasing steroidogenic enzymes activities and may prevent age-related decline in testosterone production in men. Taxifolin (13) has been shown to inhibit androgen production in immature rat Leydig cells by inhibiting the activities of Hsd3b and Cyp17a1 enzymes . However, others have reported that icariin (11) induces apoptosis in mouse Leydig tumor cells (mLTC1) , suggesting an anticancer potential. Icariin (11) has been shown to reverse the adverse effects of di(2-ethylhexyl) phtalate (DEHP) on primary Leydig cell proliferation and testosterone synthesis . Significant androgenic activity in men is achieved with Testofen supplementation through its increase of testosterone and free testosterone levels . However, men with sexual dysfunction and normal testosterone levels should not be offered TRT . One large review of studies looked at data on adults who took daily L-arginine supplements. Some studies also suggest that short-term use of L-arginine infusions may lower high blood pressure during pregnancy. The ultrasonographic biometric measurements of testicular, epididymal, and accessory genital glands in control, and L-arginine treated groups are presented in Table 1. Schematic diagram showing the experimental protocol for the effect of oral administration of rumen-protected L-arginine on the testes and accessory genital glands of rams. The rams were randomly divided into two equal groups; the control group, and rumen-protected L-arginine treated group 20 mg/Kg body weight (L-arginine pure, 25 gm, C6H14N4O2) for 30 days (Figure 1) (16). A total number of 10 apparently healthy, fertile Ossimirams with a bodyweight of 49–54 Kg and aged 2–3 years were included in this study. Arginine and blood pressure A 10% increase in RPF was noticed in placebo patients; however, the great decrease of RPF by Ang II was not affected by the L-arginine administration. A recent study composed of eight healthy subjects confirmed that L-arginine had almost no effect on their patients . Because of the increase in CAT1 mRNA and transport of L-arginine, the hypertensive effects of the NO precursor must be increased as well. The bioavailability of NO is increased by L-arginine that increases its formation and reduces its inactivation by superoxides 22,23, due to which L-arginine supplementation is suggested as a potential therapeutic approach in hypertension . This study supports that L-citrulline is effectively converted to L-arginine and is an important factor that can increase and improve NO production. While it is undeniable that l-arginine increases blood flow, which increases oxygen to the muscles and improves athletic performance. L-arginine, which supports Nitrogen Oxide activity, and other ingredients that will essentially increase testosterone are present in all of these products. L-arginine is a generic term used in the supplement industry to refer to substances that increase testosterone. The metabolism of arginine leads to the production of approximately 1–2 g of creatine per day, indicating a need for additional supply from the diet . Noteworthy, results obtained in highly trained healthy athletes are inconclusive and often demonstrate no effect of arginine preparations on power, strength and muscle mass, maximum oxygen uptake, and growth hormone and nitric oxide concentrations . Arginine, which occurs as a pure L-arginine preparation or in combination with other amino acids and their derivatives, is currently one of the most common supplements used by athletes. There is evidence that long-term L-arginine intake can increase insulin sensitivity and improve the glycemic indices29. In the intervention group of subjects receiving 2000 mg daily of L-arginine pills for 45 days and the control group participants 2000 mg daily placebo pills (maltodextrin) consumed. Levels of FBS, triglycerides, total cholesterol, LDL-c and HDL-c in L-arginine supplemented group compared with the placebo group showed statistically significant differences (P0.05) (Table 3). 3 Received L-arginine supplement 2000 mg per day during study To determine the differences in general characteristics and dietary intakes between L-arginine and placebo groups, we used an independent-samples t-test. Some users report improved energy and circulation within a few days to weeks, but noticeable changes in testosterone levels may take longer. Additionally, L-arginine’s role in protein metabolism may support muscle maintenance, which is important for older men looking to preserve strength and hormonal balance. As men age, natural testosterone levels decline, leading to symptoms like fatigue, reduced muscle mass, and lower libido. Additionally, proper protein intake and resistance training further enhance testosterone synthesis, making supplementation more effective. The final study using Asian ginseng was conducted in 80 infertile men, aged between 25 and 45 y (56). Study durations were from 2 h up to 6 mo, with 2 studies having durations of 2 h and 10 h, respectively, and the remaining studies having durations from 4 wk to 6 mo. Sample sizes ranged from 7 to 620 and ages of the male participants ranged from 18 to 79 y. The initial search identified 4384 unique studies, of which 32 randomized controlled trials were identified as eligible following assessment using the selection criteria (Figure 1) (35–66). Fatty acids can be produced endogenously or obtained from the blood, and before entering cells, they bind to albumin 52,53. It would be interesting to study the relationship between athletes who incorporate L-Carnitine supplementation and their semen quality and fertility outcomes compared to non-athlete men without any supplementation. On the other hand, the 3-week treatment group experienced positive effects regarding lipid metabolism, evoked muscle potential, and maximal oxygen uptake, leading to better athletic performance. The single-dose group experience beneficial effects regarding physical performance, lipid metabolism, muscular function, and lactate accumulation after exercise. In trans-activation, L-arginine effluence from the cells increases by the addition of cationic or neutral amino acids to the extracellular space . Therefore, an increase in L-citrulline leads to an increase in L-arginine, which leads to an enhancement in NO production. In conclusion, treatment with rumen-protected L-arginine is beneficial in improvement of rams' fertility that it could improve the testicular, accessory genital glands biometric measurements and functions, and semen quality and quantity. As a result, there was a reduction of mean blood pressure from 82 ± 2.5 to 76.3 ± 2.5 mmHg. Unless there is a disturbance of renal-pressure natriuresis to higher blood pressures, chronic hypertension will not progress . The development of hypertension is caused due to renal endothelial dysfunction and reduced NO bioavailability . The y+l mechanism, which is present in endothelial cells, is connected with CD/984F2 heavy chain. The result shows that oral citrulline decreased the brachial systolic blood pressure (-6 ± 11 mmHg), aortic systolic blood pressure (-4 ± 10 mmHg), and aortic pulse pressure (-3 ± 6 mmHg) . Binding of the NO to the COX can also cause intracellular signaling events, including oxygen diversion to non-respiratory substrates and ROS production with potentially destructive effects (158). Reduction muscle sympathetic activity causes an increase in vasodilation and skeletal muscle blood flow (138). Considering the modulation of nerve cell function by the NO in vivo and in vitro studies, it has been shown that in all brain structures, NO modulates the release of several neurotransmitters. The NO is a messenger molecule with numerous molecular targets among other servo-regulatory control functions including neurotransmission (123). A prospective, non-randomized, clinical study with 19 subfertile men revealed an improvement of sperm morphology by 38% and improvement of mannose receptor binding by 19% following treatment with 200 mg/day Pycnogenol for 90 days . No adverse effects were reported in all of the referred studies. Another combination of 80 mg Pycnogenol, 1.92g L-arginine, 1.2g citrulline and 40mg French oak wood extract (Prelox®R) a day was tested on 50 men with confirmed erectile dysfunction (ED scores 11-17) . A further double-blind, placebo-controlled, parallel group comparison investigated the effect of a combination of 60 mg Pycnogenol and 690 mg arginine (as arginine aspartate) a day on 23 Japanese men . Participants were included in this study if they were healthy, postmenopausal women aged 45 to 55 years old with no clinically significant cardiovascular disease and moderate sexual dysfunction. L-arginine and its effect on NO can lead to vasodilation and increase arterial blood flow to the genitals . As such, they utilize more healthcare services and have higher overall medical expenses due to an increased number of outpatient visits and use of prescription medications compared to patients without HSDD 7,8. Increasing awareness of female sexual dysfunction highlights a greater need for treatment strategies in women with hypoactive sexual desire disorder (HSDD) and related conditions. One study assessed vaginal pulse amplitude and found a statistically significant increase in a combination treatment group compared to placebo. Exclusion criteria were consuming any nutritional supplements (excluding multivitamins) three months before the study.Argininosuccinate lyase and argininosuccinate synthase in the liver recycles Cit into Arg to produce a Cit-Arg cycle that produces NO .The changes in the vasculogenic ED degree category during the study, for each patient in l-ARG and placebo groups, are shown in Fig.The literature was examined regarding the effects of Arg supplementation on sports performance using athletic performance outcome variables classified according to the duration of tests used.It also increased cyclic guanosine monophosphate (c-GMP), superoxide dismutase and adiponectin levels, while it decreased endothelin-1 levels and the leptin-to-adiponectin ratio.Tracking hormone levels through blood tests can help assess long-term changes.DBP, diastolic blood pressure; FMD, flow-mediated dilation; IV, intravenous; LOS, length of stay in hospital; NR, not reported; NS, not significant; OR, odds ratio; RR, relative risk; SBP, systolic blood pressure. What Is L-Arginine? Potential Benefits, Known Risks, and More By making these lifestyle changes and being mindful of your dietary choices, you can naturally boost your testosterone levels without relying on supplements. Implementing positive lifestyle changes can go a long way in supporting healthy testosterone levels. A doctor or nutritionist can help you determine if L-arginine supplements are suitable for your individual needs and guide you on the appropriate dosage. Results were reported as total means, and were collected at baseline, four weeks and eight weeks. Participants were given two tablets of Lady Prelox in the morning and 2 tablets in the evening or a matching placebo over the course of 8 weeks. Investigators required a satisfactory education level and cultural-social status were considered important for inclusion for understanding and adherence to the study protocol. Limitations of this study included a small sample size, missing or poorly defined exclusion criteria, concurrent drug use was not discussed, and the statistical test was inappropriate for the type of data that was collected. Ito et al. (2006) concluded that intervention with ArginMax had a positive effect on sexual desire scores among pre, peri, and postmenopausal women. Arginine supplements come in various product forms—capsule, tablet, powder—but are most commonly found among other ingredients in a T-booster stack. For the most part, L-Arginine is relatively safe over a long period of supplementation with an upper safety limit of around 20 g daily—although higher dosages have been deemed safe (albeit on a short-term dosage schedule).9 To maintain adequate Arginine levels throughout the day, you’ll need to aim for the 15 g – 18 g daily threshold—but no more than 10 g per serving. Supplementary Material In addition, IMCL of tibialis anterior muscle is a significant determinant of peak GH levels 79, 80. However, interventional studies are needed for more investigation of this hypothesis. Intrahepatic lipid concentration can be considered as a determinant of peak GH levels. However, you should still be sure to include foods in your diet that are rich in L-arginine.Claims like these can only legitimately be made for drugs, not dietary supplements.” .Here it was demonstrated that the stimulatory effect of ginseng extracts on DNA and protein syntheses in rat testes.29 Later studies in both rodents and humans have shown that ginseng can increase sperm count.The intake of standalone Arg supplements by well-trained athletes or healthy recreational participants does not appear to improve strength .The rationale behind the administration of l-ARG as a suitable treatment for vasculogenic ED relies on the matter of fact that l-ARG is an important donor of NO, which is a prominent molecular mediator of the penile erectile process, for the ability to induce cavernous smooth muscle relaxation, and particularly to contribute to the cavernous arteries performance and cavernous blood flow, crucial for penis erection 4, 7.As chances are high this might provide you with a counterfeit product that further can cause severe side effects.In addition, chronic intake of Arg supplements did not result in improved athletic performance in well-trained endurance athletes .Phosphorylation of ERK (p44/42 MAPK), a kinase in the MAPK family, was also increased; however, it was nonsignificant.However, its role in testosterone production remains a topic of ongoing research and debate. For LOW TESTOSTERONE, the amino acid L-arginine boosts nitric oxide production which directly parallels increasing testosterone levels. Apart from these t-boosters that contribute l-arginine, you can also stack other supplements that enhance testosterone production. Although no human study shows the direct effect of L-arginine on testosterone, some studies indirectly link it with T-boost. The study was conducted to explore the effects of L-Arginine on muscles and DNA damage among healthy rats with an arginine-deficient diet. Men with confirmed erectile dysfunction (ED) restored erectile function in clinical studies to normal scores following supplementation with Prelox® according to the questionnaire for erectile dysfunction. Molecular effects of Moringa leaf extract on insulin resistance and reproductive function in hyperinsulinemic male rats. Ho H, Shirakawa H, Giriwono PE, Ito A, Komai M. A novel function of geranylgeraniol in regulating testosterone production. Effect of cordyceps militaris supplementation on sperm production, sperm motility and hormones in sprague-dawley rats. Supplementation is often recommended for individuals seeking to enhance their physical performance, improve sexual health, or support muscle recovery. However, its role in testosterone production remains a topic of ongoing research and debate. L-Arginine is a semi-essential amino acid that plays a critical role in various physiological processes, including immune function, cardiovascular health, and muscle metabolism. Noteworthy, analyzing results according to baseline vasculogenic ED degree category, at study completion, IIEF-6 score was significantly increased in both subgroups of patients with mild–moderate and severe vasculogenic ED, whereas PSV was significantly increased only in the subgroup of patients with mild–moderate vasculogenic ED, despite a significantly lower baseline PSV in l-ARG compared to placebo group. Relative changes (Δ%) in penile erectile function from baseline (T0) to 90 days (T1) in l-arginine and placebo groups in the overall cohort, and in the subgroups of patients with baseline mild–moderate or severe vasculogenic ED, assessed at dynamic PDU Evaluation of penile erectile function at baseline (T0) and after 90 days (T1), in l-arginine and placebo subgroups of patients with baseline mild–moderate or severe vasculogenic ED, assessed at dynamic PDU An endocrine evaluation with the measurement of the most important hormones involved in the regulation of sexual function (total testosterone and prolactin) was performed at baseline to exclude the main endocrine disorders affecting penile erectile function; total testosterone levels were also re-tested at study completion. Noteworthy, the potential role of l-ARG supplementation is corroborated by the evidence that a significant proportion of patients with ED, particularly of vasculogenic etiology, are characterized by a decrease of NO production in the penile vascular endothelium, such as in the case of ED caused by diabetes and atherosclerosis 16, 17, 19, and by low l-ARG or l-CIT levels, compared to men without ED, therefore suggesting that low levels of these amino acids might increase the risk of ED by inducing the reduction of NO availability . 1 Protective effect of taurine on drug-induced male reproductive toxicity These results indicated that Pycnogenol could play a part in improvement of quality of sperms. Medication consisted of 4 tablets Prelox or 4 tablets placebo a day. Men with mild to moderate ED participated on a randomized, double-blind, placebo-controlled, parallel arm trial. In further study with 124 men the effect of Prelox was assessed over a period of 6 months . The endothelium produces a large array of factors to maintain vascular homeostasis. The results suggested that the carnitine taken up by Sertoli cells is transferred to the seminiferous tubular fluid across the blood–testis barrier (BTB). The study also investigated the ability of carnitine absorbed by Sertoli cells to cross over to the apical side of these cells. They observed that carnitine uptake across the basolateral membrane of Sertoli cells is mediated by OCTN2, facilitating the transport of carnitine through the blood–brain barrier from the blood to these cells. Caviglia et al. (2004) studied the role of carnitines at the testicular level by examining their effects on protein metabolism in rat Sertoli cells. The risk-of-bias assessment (Supplemental Tables 1 and 2) revealed some concerns for most of the included studies. A total of 301 participants were recruited for the studies involving Tribulus terrestris, with ages ranging from 18 to 65 y and sample sizes ranging from 21 to 180 participants. Two studies used patented extracts, Trib Gold, manufactured by Nerhadou International, standardized to contain up to 45% steroidal saponins (extract source not provided) (39), and Tribestan, manufactured by Sopharma, delivering a minimum of 675 mg furostanol saponins (from overground parts of the herb) (48). Three studies used the Testofen® extract, manufactured by GencorTM (also known as Fenu-FG) (details of extract preparation not provided) (57, 58, 63) and the other 3 studies used the extracts IND9, manufactured by Indus Biotech® (53), Furosap®, manufactured by Chemical Resources (CHERESO) (42), and an extract standardized for Grecunin, manufactured by Indus Biotech® (64) (details of all extract preparations not provided).