Gross saponin of Tribulus terrestris improves erectile dysfunction in type 2 diabetic rats by repairing the endothelial function of the penile corpus cavernosum

Mimosa pudica Linn. extract improves aphrodisiac performance in diabetes-induced male Wister rats

Male sexual dysfunction is considered one of the major consequences of diabetes mellitus. The medicinal plant, Mimosa pudica Linn. is believed to have numerous therapeutic effects, including anti-diabetic, anti-obesity, aphrodisiac, and a sexual behaviour-enhancing properties. In the present study, the significant effect of ethanolic extract of M. pudica L. to scavenge excessive free radicals and alleviate the deleterious effects of alloxan-induced diabetes on the male sexual system of rats was demonstrated. The rats treated with the M. pudica L. extract recovered their body weight, the weight of their reproductive organs, the characteristics of the sperm and the histocellular arrangement of the testes. In addition, significant levels of hormones (testosterone, follicle-stimulating hormone and luteinising hormone) increased in both serum and testicular homogenates of male diabetic rats treated with M. pudica L. extract. Further, antioxidant enzymes, SOD, CAT, GSH, and GPx levels are increased, and oxidative stress markers MDA and ROS are reduced in both serum and testicular homogenates of M. pudica L. extract treated male rats. Furthermore, an in silico molecular docking study was performed to predict high potential compounds of M. pudica L. extract against the PDE5 receptor. Two bioactive compounds, namely 3-Dibenzofuranamine (-11.1 kcal × mol-1), Stigmasta-7,16-dien-3-ol (-10.4 kcal × mol-1) showed the highest binding affinities with PDE5 enzyme, much higher than the reference drug sildenafil (-9.9 kcal × mol-1). According to these findings, bioactive compounds rich in ethanolic extract of M. pudica L. have significant aphrodisiac performance in diabetic rats.Communicated by Ramaswamy H. Sarma.

Mechanism of Traditional Chinese Medicine extract in the treatment of diabetic erectile dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic erectile dysfunction (DED) is a prevalent but often overlooked microvascular complication of type 2 diabetes mellitus (T2DM), with strong associations to cardiovascular disease. The pathophysiology of erectile dysfunction (ED) in T2DM patients is more intricate than in non-diabetic individuals, likely involving multiple pathogenic mechanisms such as endothelial dysfunction, vascular alterations, neuropathy, and oxidative stress. Traditional Chinese Medicine (TCM) has long been utilized in the management of DED, drawing on an extensive body of clinical experience. In TCM, DED is typically attributed to imbalances such as renal yang deficiency or insufficiencies in qi and blood. Herbal therapies within the TCM framework offer a multifaceted approach to treatment, targeting not only the replenishment of kidney yang and the regulation of qi and blood but also incorporating strategies for glycemic control and renal protection. This holistic approach has demonstrated effectiveness in alleviating erectile dysfunction in diabetic patients, thereby improving quality of life. However, the complexity of Chinese herbal formulations, with their diverse bioactive constituents, complicates the identification of specific active compounds and the mechanistic understanding of their therapeutic actions. This complexity has contributed to ongoing skepticism regarding the clinical utility of TCM and herbal remedies in the treatment of DED.

AIM OF THE STUDY

This study aimed to investigate the pathological mechanisms underlying the therapeutic effects of TCM in the treatment of DED, with a specific focus on the associated signaling pathways. By elucidating these mechanisms, the study seeks to provide a scientific basis for novel therapeutic strategies and enhance the viability of TCM-based approaches for DED management. Future research should prioritize the development of efficacious Chinese patent medicines tailored for the treatment of DED.

METHODS

This study utilizes keywords such as "diabetic erectile dysfunction", "signaling pathways", "traditional Chinese Medicine", "bioactive compounds", "herbal", "herbal monomers", and "herbal extracts" to conduct a comprehensive literature search in databases including Embase, PubMed, Web of Science, CNKI, Wanfang, and VIP, spanning all relevant publications up to February 2024.

RESULTS

It has been demonstrated that TCM extract can treat the DED by influencing the signaling pathways involved.

CONCLUSION

A comprehensive literature review was conducted across multiple databases, followed by rigorous screening, exclusion, summarization, synthesis, and analysis of relevant studies. The results indicate that TCM for DED primarily targets key pathological features, including endothelial dysfunction, vascular and neural abnormalities, and oxidative stress. The underlying mechanisms involve the NO/cGMP, eNOS, and PI3K/Akt/mTOR signaling pathways, contributing to significant improvements in erectile function. These findings provide a scientific basis for the use of TCM in DED, offering viable therapeutic options and innovative strategies to advance TCM-based treatment approaches. Furthermore, TCM exhibits notable potential in mitigating the pathological progression of DED. The pharmacological mechanisms and molecular signaling pathways of TCM extracts have been extensively investigated, underscoring their high value for clinical research and therapeutic development.

Identification of fibrosis-related genes and biomarkers in diabetic erectile dysfunction

Background

Diabetic erectile dysfunction (DMED) has a high incidence and is poorly treated.

Aim

This study investigates fibrosis's genetic profiling and explores potential mechanisms for DMED.

Methods

The DMED model was constructed in rats using streptozotocin. Erectile function was quantified using cavernous nerve electrostimulation. Fibrosis was evaluated using Masson's staining. RNA-seq was employed to analyze differentially expressed genes and fibrosis-related genes (FRGs) were acquired. Function enrichment analyses were performed, and genetic interaction was analyzed. Hub FRGs were screened using machine learning algorithms and Cytoscape tools and validated in Gene Expression Omnibus databases. Moreover, biological roles and subpopulation distribution of hub FRGs were determined.

Outcomes

Fibrosis-related genetic functions may play a vital role in DMED.

Results

Based on comprehensive analysis, 45 differentially expressed FRGs were identified. These genes participate in regulating smooth muscle cell proliferation, vasoconstriction, and collagen-associated activities. Final analyses identified and validated a core gene signature comprising TIMP1, BMP7, and POSTN. They were closely associated with diabetic complications-related signaling pathways and extracellular matrix-receptor interaction.

Clinical Translation

The identified fibrosis-related gene signature may serve as the novel biomarkers for treating DMED.

Strengths and Limitations

The study is the first to investigate the genetic profiles behind fibrosis and DMED using comprehensive approaches. However, the validation is not adequate and more animal experiments are needed.

Conclusion

The gene profiling and biological functions of FRGs in DMED were identified. These results broaden the understanding of fibrosis in DMED.

The Effect of the Combination of Ginseng, Tribulus Terrestris, and L-arginine on the Sexual Performance of Men with Erectile Dysfunction: a randomized, double-blind, parallel, and placebo-controlled clinical trial

Objectives

Nitric oxide is the most important mediator of penile erection after the onset of sexual excitement. It activates cyclic guanosine monophosphate (cGMP), increasing penile blood flow. Most pharmaceutical medications prevent enzyme phosphodiesterase type 5 (PDE-5) from breaking down cGMP, thus keeping its level high. However, due to the adverse effects of pharmacological therapies, herbal drugs that improve sexual function have gained attention recently. This study aimed to investigate the combined effects of ginseng, Tribulus terrestris, and L-arginine amino acid on the sexual performance of individuals with erectile dysfunction (ED) using the 5-item version of the International Index of Erectile Function (IIEF-5) questionnaire.

Methods

Over three months, 98 men with erectile dysfunction were randomly assigned to receive either 500 mg of herbal supplements or placebo pills. Each herbal tablet contained 100 mg of protodioscin, 35 mg of ginsenosides, and 250 mg of L-arginine.

Results

The results showed that the changes in the average scores of ILEF-5 within each group before and after the intervention indicated that all parameters related to the improvement of sexual function in patients with erectile dysfunction improved in the herbal treatment group (p < 0.001). The herbal group significantly improved IIEF-5 scores in non-diabetics (p < 0.05). However, there was no significant difference in the changes of IIEF-5 scores between the two intervention and control groups in diabetic patients.

Conclusion

In conclusion, ginseng, Tribulus terrestris, and L-arginine have properties that increase energy and strengthen sexual function, making them suitable for patients with sexual disorders.

Lauric acid attenuates hepato-metabolic complications and molecular alterations in high-fat diet-induced nonalcoholic fatty liver disease in rats

Nonalcoholic fatty liver disease (NAFLD) has emerged as a major chronic liver illness characterized by increase of lipid content in the liver. This study investigated the role of lauric acid to treat NAFLD in male adult Sprague Dawley rats. In this study, to induce NAFLD in the rats, a high-fat diet (HFD) was administered for eight consecutive weeks. Lauric acid groups received lauric acid (250 and 500 mg/kg; orally), concurrently with HFD for eight consecutive weeks. Lauric acid could ameliorate the serum levels of TG, TC, ALT, AST, blood glucose, and insulin. Moreover, lauric acid significantly elevated the levels of SOD, GSH, catalase, and IL-10. Additionally, it lowered the hepatic levels of MDA, ROS, MPO, 4-HNE, interleukin (IL)-1β, and tumor necrosis factor (TNF-α). Furthermore, lauric acid significantly up-regulated the hepatic expression of IRS1, AMPK, PI3K, and SIRT1 genes. In parallel, lauric acid could improve the histopathological picture of the liver and reduce the liver apoptosis via decreasing the expression of annexin V (Anx V). Finally, our data proposed that lauric acid could be an effective candidate for the NAFLD treatment.

ROUX-en-Y gastric bypass surgery improves metabolic syndrome-related erectile dysfunction in mice via the IRS-1/PI3K/AKT/eNOS pathway

Objective

Although many clinical studies have shown that ROUX-en-Y gastric bypass (RYGB) surgery significantly improves metabolic syndrome-related erectile dysfunction (MED), the role and mechanism are unclear.

Aim

In this study we used a mouse model to explore how RYGB improves MED induced by a high-fat diet (HFD).

Methods

We established a mouse model of metabolic syndrome by feeding an HFD for 16 weeks. The mice were randomly assigned to the standard chow diet (SCD), HFD, or RYGB groups. Body weight, fasting blood glucose, plasma insulin, and total plasma cholesterol were analyzed. Erectile responses were evaluated by determining the mean systolic blood pressure and the intracavernosal pressure (ICP). Penile histologic examination (Masson's trichrome and immunohistochemical stain) and Western blot were performed.

Result

Compared with the SCD group, the ICP in the sham group was significantly lower, and the ICP of the RYGB was significantly increased. Masson's trichrome and immunohistochemical staining showed that the content of endothelium and smooth muscle in the corpus cavernosum of mice with MED was significantly reduced. Western blot analysis showed a significant decrease in α-smooth muscle actin and a significant increase in osteopontin in penile tissue in the sham group, which was improved by RYGB surgery. Furthermore, RYGB significantly increased IRS-1/PI3K/Akt/eNOS phosphorylation.

Clinical Translation

In this study we explored the mechanism of bariatric surgery to improve erectile dysfunction associated with metabolic syndrome and provided a theoretical basis for clinical research.

Strengths and Limitations

First, we did not investigate the mechanism by which RYGB affects the IRS-1/PI3K/Akt/eNOS signaling pathway. Second, the effect of the IRS-1/PI3K/Akt/eNOS signaling pathway on the function of corpus cavernosum endothelial cells and smooth muscle cells remains to be investigated in cellular studies.

Conclusion

This study demonstrated that RYGB may not only improve metabolic parameters but also restore erectile function in MED patients. The mechanism of the therapeutic effect of RYGB may be reactivation of the IRS-1/PI3K/Akt/eNOS pathway.

Understanding exosomes: Part 2-Emerging leaders in regenerative medicine

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of diseases/conditions. Over 5000 publications are currently being published yearly on this topic, and this number is only expected to dramatically increase as novel therapeutic strategies continue to be developed. Today exosomes have been applied in numerous contexts including neurodegenerative disorders (Alzheimer's disease, central nervous system, depression, multiple sclerosis, Parkinson's disease, post-traumatic stress disorders, traumatic brain injury, peripheral nerve injury), damaged organs (heart, kidney, liver, stroke, myocardial infarctions, myocardial infarctions, ovaries), degenerative processes (atherosclerosis, diabetes, hematology disorders, musculoskeletal degeneration, osteoradionecrosis, respiratory disease), infectious diseases (COVID-19, hepatitis), regenerative procedures (antiaging, bone regeneration, cartilage/joint regeneration, osteoarthritis, cutaneous wounds, dental regeneration, dermatology/skin regeneration, erectile dysfunction, hair regrowth, intervertebral disc repair, spinal cord injury, vascular regeneration), and cancer therapy (breast, colorectal, gastric cancer and osteosarcomas), immune function (allergy, autoimmune disorders, immune regulation, inflammatory diseases, lupus, rheumatoid arthritis). This scoping review is a first of its kind aimed at summarizing the extensive regenerative potential of exosomes over a broad range of diseases and disorders.

Leech-Centipede Granules Suppress EndMT to Improve Erectile Dysfunction in Rats with Diabetes Mellitus via TGF-β/Smad Pathway

OBJECTIVE

To investigate whether Leech-Centipede (LC) Granules can improve erectile function in rats with diabetes mellitus-associated erectile dysfunction (DMED) through endothelial-to-mesenchymal transition (EndMT) inhibition.

METHODS

Components of LC Granules were identified via ultra-high-performance liquid chromatography. Thirty male Sprague Dawley rats were injected with streptozotocin and fed continuously for 8 weeks to establish the DMED rat model. Rats with erectile dysfunction symptoms diagnosed using apomorphine were divided into DMED and low-, medium-, and high-doses LC groups (n=6 in each). The negative control (NC, n=6) and DMED groups were given 5 mL of deionized water via intragastric gavage, and the low-, medium- and the high-doses LC groups were administered LC at 1.6, 3.2, and 6.4 g/kg, respectively, via intragastric gavage for 4 weeks. The intracavernous pressure (ICP), mean arterial pressure (MAP), and nitric oxide (NO) levels in cavernous tissue were measured for each group. Quantitative reverse transcription-polymerase chain reaction and Western blot were used to detect mRNA and protein expressions of endothelial and mesenchymal markers. Immunofluorescence staining was used to observe α-SMA, and Masson's trichrome staining was performed to determine the myofiber/collagen ratio.

RESULTS

A total of 474 active components were identified. After treatment, the ICP/MAP value and NO level were significantly higher in the medium- and high-dose LC groups than in the DMED group (P<0.05). Compared with the DMED groups, the medium- and high-dose groups LC significantly increased and decreased endothelial and mesenchymal markers expression, respectively (P<0.05). Tumor growth factor (TGF)β R II, p-Smad2, and p-Smad3 levels were considerably higher following diabetes onset but reduced following LC intervention (P<0.05), except for TGF β 1 (P>0.05). α-SMA expression was significantly higher in the DMED group and was reduced in all LC intervention groups (P>0.05). The myofiber/collagen ratio in the LC groups was higher than that in the DMED group but lower than that in the NC group (all P<0.05).

CONCLUSIONS

LC Granules may improve the erectile function of DMED rats by suppressing TGF-β/Smad pathway to reverse EndMT.

Traditional chinese medicine to prevent and treat diabetic erectile dysfunction

Diabetic erectile dysfunction (DED) is one of the most common complications of diabetes mellitus. However, current therapeutics have no satisfactory effect on DED. In recent years, traditional Chinese medicine (TCM) has shown good effects against DED. By now, several clinical trials have been conducted to study the effect of TCM in treating DED; yet, the underlying mechanism is not fully investigated. Therefore, in this review, we briefly summarized the pathophysiological mechanism of DED and reviewed the published clinical trials on the treatment of DED by TCM. Then, the therapeutic potential of TCM and the underlying mechanisms whereby TCM exerts protective effects were summarized. We concluded that TCM is more effective than chemical drugs in treating DED by targeting multiple signaling pathways, including those involved in oxidation, apoptosis, atherosclerosis, and endothelial function. However, the major limitation in the application of TCM against DED is the lack of a large-scale, multicenter, randomized, and controlled clinical trial on the therapeutic effect, and the underlying pharmaceutical mechanisms also need further investigation. Despite these limitations, clinical trials and further experimental studies will enhance our understanding of the mechanisms modulated by TCM and promote the widespread application of TCM to treat DED.

Ganoderma lucidum polysaccharide ameliorated diabetes mellitus-induced erectile dysfunction in rats by regulating fibrosis and the NOS/ERK/JNK pathway

Background

Diabetes mellitus-induced erectile dysfunction (DMED) is a frequent complication of diabetes mellitus (DM), with limited therapy at present. This study aimed to explore the role and mechanism of Ganoderma lucidum polysaccharide (GLP) on DMED.

Methods

DMED was induced in the experimental rats [male 12-week-old Sprague-Dawley (SD) rats] by treatment with streptozotocin (60 mg/kg) and apomorphine (APO). Next, rats in the GLP low dose (GLP-L)/GLP high dose (GLP-H) groups were treated with GLP (100 or 400 mg/kg/d, respectively) for 8 weeks. Subsequently, erectile function was assessed by APO and electrostimulation of the cavernous nerve (CN). Serum or penile testosterone (T), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and cyclic guanosine monophosphate (cGMP) contents were evaluated by enzyme-linked immunosorbent assay (ELISA). The levels of oxidative stress indicators in the corpus cavernosum (CC) were measured by corresponding kits, and histological changes in the CC were observed by hematoxylin-eosin (HE) and Masson staining. Additionally, the apoptosis index, caspase-3, caspase-9, and eNOS expression, and mitochondrial membrane potential (MMP) were also detected. Furthermore, quantitative polymerase chain reaction (qPCR) and western blot assays were conducted to determine the NOS, TGF-β1 mRNA expression, ERK1/2, eNOS, JNK phosphorylation, and arginase II protein expression.

Results

The erectile function test revealed that erectile dysfunction (ED) was alleviated in the DMED rats following treatment with GLP. Moreover, GLP upregulated the T and cGMP content, improved the oxidative stress and histological injuries of CC, and also inhibited the apoptosis and MMP loss of penile tissues in DMED rats. Furthermore, GLP treatment enhanced the mRNA expression of NOS and TGF-β1 and suppressed the phosphorylation of ERK1/2, eNOS, and JNK, as well as the protein expression of arginase II in DMED rats.

Conclusions

GLP ameliorated DMED by repairing the CC pathological damage and upregulating NOS expression and ERK/JNK phosphorylation, indicating that GLP may be a candidate drug for DMED therapy.

Exosomes as Promising Nanostructures in Diabetes Mellitus: From Insulin Sensitivity to Ameliorating Diabetic Complications

Diabetes mellitus (DM) is among the chronic metabolic disorders that its incidence rate has shown an increase in developed and wealthy countries due to lifestyle and obesity. The treatment of DM has always been of interest, and significant effort has been made in this field. Exosomes belong to extracellular vesicles with nanosized features (30-150 nm) that are involved in cell-to-cell communication and preserving homeostasis. The function of exosomes is different based on their cargo, and they may contain lipids, proteins, and nucleic acids. The present review focuses on the application of exosomes in the treatment of DM; both glucose and lipid levels are significantly affected by exosomes, and these nanostructures enhance lipid metabolism and decrease its deposition. Furthermore, exosomes promote glucose metabolism and affect the level of glycolytic enzymes and glucose transporters in DM. Type I DM results from the destruction of β cells in the pancreas, and exosomes can be employed to ameliorate apoptosis and endoplasmic reticulum (ER) stress in these cells. The exosomes have dual functions in mediating insulin resistance/sensitivity, and M1 macrophage-derived exosomes inhibit insulin secretion. The exosomes may contain miRNAs, and by transferring among cells, they can regulate various molecular pathways such as AMPK, PI3K/Akt, and β-catenin to affect DM progression. Noteworthy, exosomes are present in different body fluids such as blood circulation, and they can be employed as biomarkers for the diagnosis of diabetic patients. Future studies should focus on engineering exosomes derived from sources such as mesenchymal stem cells to treat DM as a novel strategy.

Molecular Action of Herbal Medicine in Physiology of Erection and its Dysfunction

Erection is a physiological process that involves vascular, hormonal, and nervous factors. Erectile dysfunction is one of the male sexual problems that occur globally and is reported to affect men's quality of life. Herbal plants have been widely used for disease treatment, including the problem of erectile dysfunction. This paper aims to review the molecular potential of various plants in the physiology of erection and to treat erectile dysfunction. The literature search was carried out through the Pubmed and Google Scholar databases regarding the molecular mechanisms of herbal plants and their potential involvement in the physiology of erection and overcoming erectile dysfunction. This paper focuses on six herbal plants: Panax ginseng, Ginkgo biloba, Epimedium, Black pepper, Tribulus terrestris, and Eurycoma longifolia. The six herbal plants have involvement in the erection process and have molecular potential in the treatment of erectile problems

Uncovering the mechanisms of leech and centipede granules in the treatment of diabetes mellitus-induced erectile dysfunction utilising network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus-induced erectile dysfunction (DMED) is one of the most common complications of diabetes mellitus. Leech and centipede granules (LCG) have traditionally been used as blood-activating agents in various ethnomedicinal systems of East Asia, especially in China. It is often used to regulate bodily functions and considered as adjuvant therapy for promoting blood circulation, alleviating blood coagulation, activating meridians, and relieving stasis.

AIM OF THE STUDY

This study aimed to identify potential genes and mechanisms of LCG on DMED from the network pharmacological perspective.

MATERIALS AND METHODS

The active components of LCG were identified by UHPLC-Q-TOF-MS, TCMID, and the BATMAN-TCM databases, and the disease targets of DMED were obtained from the DisGeNET, CooLGeN, GeneCards databases. After identifying DMED targets of LCG, a protein-protein interaction (PPI) network was constructed. Hub genes and significant modules were identified via the MCODE plug-in of Cytoscape software. Then, significant signaling pathways of the modules were identified using the Metascape database. The probable interaction mode of compounds-hub genes is examined using Molecular Operating Environment (MOE) docking software. Besides, we investigated the effects and mechanisms of LCG on improving erectile function in the streptozotocin (STZ)-induced diabetic rats model.

RESULTS

Combined UHPLC-Q-TOF-MS analysis with network pharmacology study, 18 active compounds were selected for target prediction. There are 97 common target genes between LCG and DMED. Enrichment of the KEGG pathway mainly involves in the calcium signaling pathway, NF-kappa B signaling pathway, cGMP-PKG signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway, and mTOR signaling pathway. Nine hub genes were regulated by LCG in DMED, including CXCL8, NOS3, CRH, TH, BDNF, DRD4, ACE, CNR1, and HTR1A. The results of molecular docking analysis showed that the tyrosin, ursolic acid, and L-Histidine has a relatively stable interaction with corresponding hub genes via generating hydrogen bonds, H-π, and π-π interactions. Significantly, the results in docking predicted a higher affinity of vardenafil to the hub genes compared to the tyrosin, ursolic acid, and L-Histidine. Furthermore, LCG increased the testosterone, erection frequency, the ratio of ICP and MAP, SOD, cGMP, cAMP as well as decreased the MDA, and AGEs expression levels. And, LCG ameliorated the histological change of penile tissues in DMED rats. Hence, LCG attenuates oxidative stress, increases NO production; For the mechanism exploration, LCG could significantly upregulate the mRNA and protein expression of CNR1, NOS3, CRH, TH, BDNF, and DRD4, whereas CXCL8, ACE, and HTR1A levels were significantly higher than those in the DMED group. Moreover, LCG activates the NO/cGMP/PKG pathway, PI3K/Akt/nNOS pathway, cAMP/PKA pathway, and inhibits the HIF-1α/mTOR pathway to improve erectile function.

CONCLUSIONS

Our results suggest that LCG maybe offer a new therapeutic basis for the treatment of DMED via altering the gene expression of involved metabolic pathways.

The Possible Role of Saponin in Type-II Diabetes- A Review

BACKGROUND

The possible role of secondary metabolites in the management of diabetes is a great concern and constant discussion. This characteristic seems relevant and should be the subject of thorough discussion with respect to saponin.

OBJECTIVE

The current data mainly focus on the impact of saponin in the treatment of type-II diabetes. The majority of studies emphasize on other secondary metabolites such as alkaloids and flavonoids, but very few papers are there representing the possible role of saponin as these papers express the narrow perspective of saponin phytoconstituents but lacking in providing the complete information on various saponin plants. The aim of the study was to summarize all available data concerning the saponin containing plant in the management of type-II diabetes.

METHODS

All relevant papers on saponin were selected. This review summarizes the saponin isolation method, mechanism of action, clinical significance, medicinal plants and phytoconstituents responsible for producing a therapeutic effect in the management of diabetes.

RESULTS

The saponin is of high potential with structural diversity and inhibits diabetic complications along with reducing the hyperglycemia through different mechanisms thereby providing scope for improving the existing therapy and developing the novel medicinal agents for curing diabetes.

CONCLUSION

Saponins having potential therapeutic benefits and are theorized as an alternative medication in decreasing serum blood glucose levels in the patient suffering from diabetes.

Tribulus terrestris Ameliorates Oxidative Stress-Induced ARPE-19 Cell Injury through the PI3K/Akt-Nrf2 Signaling Pathway

Oxidative stress on retinal pigment epithelial (RPE) cells has been confirmed to play a crucial role in the development and progression of age-related macular degeneration (AMD) or other retinal degenerative diseases. Tribulus terrestris (TT) is a Chinese traditional herb medicine, which has been used for the treatment of ocular diseases for many centuries. In this study, we investigated the underlying mechanisms of TT and examined its ability to protect and restore the human retinal pigment epithelial cells (ARPE-19) against H₂O₂-induced oxidative stress. Our data show that 200 μg/mL of ethanol extract of Tribulus terrestris (EE-TT) significantly increased the cell viability and prevented the apoptosis of H₂O₂-treated ARPE-19 cells through the regulation of Bcl2, Bax, cleaved caspase-3, and caspase-9. Treatment with EE-TT also significantly decreased the upregulated reactive oxygen species (ROS) activities and increased the downregulated superoxide dismutase (SOD) activities induced by H₂O₂ in ARPE-19 cells. Additionally, H₂O₂ at 1 mM significantly decreased the mRNA expression levels of Nrf2, CAT, SOD1, SOD2, HO-1, GST-pi, NQO1, and GLCM in ARPE-19 cells; however, treatment with EE-TT reversed the downregulated mRNA expression levels of all these genes induced by H₂O₂. Furthermore, treatment with 200 μg/mL EE-TT alone for 24 h significantly increased Nrf2, HO-1, NQO1, and GCLM mRNA expressions in ARPE-19 cells when compared with untreated control cells. Pretreatment with the inhibitor of PI3K/Akt signaling (LY294002) completely blocked these EE-TT-upregulated mRNA expressions and abolished the improvement of cell viability in H₂O₂-treated ARPE-19 cells. These findings all suggest that Tribulus terrestris has significant antioxidant effects on oxidative stressed ARPE-19 cells through regulating PI3K/Akt-Nrf2 signaling pathway.

A Comprehensive Review of the Phytochemical, Pharmacological, and Toxicological Properties of Tribulus terrestris L

The general spread of Tribulus terrestris L. (South Africa, Australia, Europe, and India), the high content of active ingredients (in particular sterol saponins, as well as flavonoids, tannins, terpenoids, phenol carboxylic acids, and alkaloids), and its frequent uses in folk medicine, and as food supplements highlight the importance of evaluating its phytopharmacological properties. There are miscellaneous hypotheses that the species could have a high potential for the prevention and improvement of various human conditions such as infertility, low sexual desire, diabetes, and inflammatory diseases. Worldwide, numerous herbal supplements are commercialized with indications mostly to improve libido, sexual performance in both sexes, and athletic performance. Phytochemical studies have shown great disparities in the content of active substances (in particular the concentration of furostanol and spirostanol saponoside, considered to be the predominant active ingredients related to the therapeutic action). Thus, studies of experimental pharmacology (in vitro studies and animal models in vivo) and clinical pharmacology (efficacy and safety clinical trials) have sometimes led to divergent results; moreover, the presumed pharmacodynamic mechanisms have yet to be confirmed by molecular biology studies. Given the differences observed in the composition, the plant organ used to obtain the extract, the need for selective extraction methods which are targeted at the class of phytocompounds, and the standardization of T. terrestris extracts is an absolute necessity. This review aims to highlight the phytochemical, pharmacological, and toxicological properties of T. terrestris, with a focus on the contradictory results obtained by the studies conducted worldwide.