Antioxidant and nephroprotection activities of Combretum micranthum: A phytochemical, in-vitro and ex-vivo studies

Combretum micranthum G. Don (Combretaceae): A Review on Traditional Uses, Phytochemistry, Pharmacology and Toxicology

Combretum micranthum (Combretaceae) is a medicinal plant widely known and used in Africa to treat a variety of conditions such as diabetes, fever, coughs, bronchitis, diarrhea, pain, malaria and liver disorders, among others. Due to its wide traditional use, in this review, published scientific reports on its composition and pharmacological properties were explored by conducting a literature search of databases. To date, 155 organic compounds including 34 flavonoids, 16 phenolic acids, 14 alkaloids, 15 fatty acids, 14 terpenoids/steroids, 24 amino acids, 8 carbohydrate substances and 30 other organic compounds have been identified from this plant. In addition to these organic compounds, 6 minerals (potassium nitrate, calcium, magnesium, potassium, sodium, iron and zinc) have also been reported. In vitro and in vivo studies have shown that these phytochemicals and plant extracts have a wide range of pharmacological potential, including antibacterial, antiviral, antioxidant, antidiabetic, anti-inflammatory, analgesic, antihypertensive, nephroprotective, hepatoprotective, anxiolytic, anti-cholinesterase and antidiarrheal activities. Additionally, no harmful effects have been revealed through studies. Thus, this study could constitute a valuable reference for the valorization of C. micranthum in the pharmaceutical industry.

Antioxidant and Antibacterial Activities of the Leaf and Stem Extracts of Combretum molle (R. Br. ex G. Don.) Engl. & Diels

Medicinal plants offer reasonable and accessible alternatives to synthetic drugs and are often devoid of the adverse side effects, toxicity, and pathogenic resistance associated with synthetic medicine. Combretum molle has been utilized in African traditional medicinal practices and purportedly contains bioactive compounds with medicinally beneficial effects. This study investigated the hexane, chloroform, and methanol leaf and stem extracts for their antioxidant properties using the 2,2'-diphenyl-1-picrylhydrazyl radical scavenging and ferric-reducing antioxidant power assays. The study additionally analyzed the methanol extracts for their antibacterial activity against Gram-negative Escherichia coli (ATCC 25922) and Gram-positive Staphylococcus aureus (ATCC 25923) bacteria using agar well diffusion. Relative to the scavenging activity of the ascorbic acid control (79.15 ± 0.63% at 15 µg/mL to 94.61 ± 0.12% at 240 µg/mL), the plant's radical scavenging activities were exceptionally high in the methanolic leaf and stem extracts (p < 0.05), ranging from 94.58 ± 1.10% at 15 µg/mL to 99.22 ± 0.30% at 240 µg/mL and 91.57 ± 1.71% at 15 µg/mL to 99.60 ± 0.20% at 240 µg/mL, respectively, suggesting a strong capacity to donate hydrogen ions. High scavenging activities were additionally observed in the chloroform stem (78.68 ± 1.18% at 15 µg/mL to 98.14 ± 1.22% at 240 µg/mL) and hexane leaf (72.12 ± 4.38% at 15 µg/mL to 89.87 ± 1.50% at 240 µg/mL) extracts (p < 0.05). All extracts exhibited poor ferric-reducing abilities in relation to the gallic acid control (100 ± 0.00%) at all concentrations (p < 0.05). The leaf and stem extracts exhibited broad-spectrum antibiotic capabilities against both tested strains, with significant activity at higher concentrations (p < 0.05). Overall, both the leaf and stem extracts of C. molle exhibited similar antioxidant and antibacterial activities. These findings warrant further pharmacological research on C. molle for potential drug development.

Phytochemical Composition of Combretum molle (R. Br. ex G. Don.) Engl. & Diels Leaf and Stem Extracts

The demand for medicinal plants is on a rise due to their affordability, accessibility and relatively non-toxic nature. Combretum molle (Combretaceae) is used in African traditional medicine to treat a number of diseases. This study aimed to screen the phytochemical composition of the hexane, chloroform and methanol extracts of C. molle leaves and stems using qualitative phytochemical screening. Additionally, the study aimed to identify the functional phytochemical groups, determine the elemental composition and provide a fluorescence characterization of the powdered leaves and stems by performing Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX) microanalyses and fluorescence microscopy. Phytochemical screening revealed the presence of alkaloids, flavonoids, phenolic compounds, polyphenols, terpenoids, tannins, coumarins, saponins, phytosterols, gums, mucilage, carbohydrates, amino acids and proteins within all leaf and stem extracts. Lipids and fixed oils were additionally present within the methanol extracts. FTIR demonstrated significant peaks in absorption frequency in the leaf at wavelengths of 3283.18, 2917.81, 1617.72, 1318.83, 1233.97, 1032.32 and 521.38 cm^-1, and in the stem at 3318.91, 1619.25, 1317.13, 1032.68, 780.86 and 516.39 cm^-1. These corresponded to the functional groups of chemical compounds including alcohols, phenols, primary amines, alkyl halides, alkanes and alkyl aryl ethers, corroborating the presence of the detected phytochemicals within the plant. EDX microanalyses showed the elemental composition of the powdered leaves (68.44% C, 26.72% O, 1.87% Ca, 0.96% Cl, 0.93% Mg, 0.71% K, 0.13% Na, 0.12 % Mn and 0.10% Rb) and stems (54.92% C, 42.86% O, 1.7% Ca, 0.43% Mg and 0.09% Mn). Fluorescence microscopy provided a characteristic evaluation of the plant in its powdered form and revealed distinct colour changes in the material when treated with various reagents and viewed under ultraviolet light. In conclusion, the phytochemical constituents of the leaves and stems of C. molle confirm the suitability of this species for use in traditional medicine. The findings from this study suggest the need to validate the use of C. molle in the development of modern medicines.

Cytoprotective remedies for ameliorating nephrotoxicity induced by renal oxidative stress

AIMS

Nephrotoxicity is the hallmark of anti-neoplastic drug metabolism that causes oxidative stress. External chemical agents and prescription drugs release copious amounts of free radicals originating from molecular oxidation and unless sustainably scavenged, they stimulate membrane lipid peroxidation and disruption of the host antioxidant mechanisms. This review aims to provide a comprehensive collection of potential cytoprotective remedies in surmounting the most difficult aspect of cancer therapy as well as preventing renal oxidative stress by other means.

MATERIALS AND METHODS

Over 400 published research and review articles spanning several decades were scrutinised to obtain the relevant data which is presented in 3 categories; sources, mechanisms, and mitigation of renal oxidative stress.

KEY-FINDINGS

Drug and chemical-induced nephrotoxicity commonly manifests as chronic or acute kidney disease, nephritis, nephrotic syndrome, and nephrosis. Renal replacement therapy requirements and mortalities from end-stage renal disease are set to rapidly increase in the next decade for which 43 different cytoprotective compounds which have the capability to suppress experimental nephrotoxicity are described.

SIGNIFICANCE

The renal system performs essential homeostatic functions that play a significant role in eliminating toxicants, and its accumulation and recurrence in nephric tissues results in tubular degeneration and subsequent renal impairment. Global statistics of the latest chronic kidney disease prevalence is 13.4 % while the end-stage kidney disease requiring renal replacement therapy is 4-7 million per annum. The remedial compounds discussed herein had proven efficacy against nephrotoxicity manifested consequent to impaired antioxidant mechanisms in preclinical models produced by renal oxidative stress activators.

Anti-fertility effect of Aerva lanata crude extract in male Dams offspring: An experimental study

Background

Aerva lanata, a herb used as food and also consumed as a tonic by pregnant women to relieve stomach pains and prevent miscarriage. In addition to other characterized properties, it possesses antifertility and anti-implantation activities.

Objective

This study investigates the testicular toxicity of the testes of offsprings of Dams treated with crude aqueous extract of Aerva lanata.

Materials and Methods

25 pregnant Wistar rats (Dams) weighing 180-240 gr were randomly earmarked into 5 groups (n = 5/each). Group A served as control; groups B, C, D, and E received 200, 400, 800, and 1000 mg/kg body weight of Aerva lanata extract, respectively, beginning from 12 th to 19 th day of gestation. The pups (delivered of Dams) were weighed, observed, and sacrificed 6 wk post-parturition. The testes of the male pups were obtained for histological procedures the testis histology was examined.

Results

No gross malformation was observed in the treatment groups, the number of pups/litter was significantly reduced in group E (p= 0.01), pups weight analysis showed a significant reduction in groups C and E (p= 0.04, and 0.02 respectively), and the mean pup testes weight was significantly reduced in groups B, C, D, and E (p= 0.03, 0.03, 0.01, and < 0.001 respectively) when compared with control. Histologically, the treated pup testes tissues showed varying degrees of disruption and distortion of the cellular arrangements of the germinal epithelium in a dose dependent manner compared to the control.

Conclusion

The study revealed a testicular toxicity and possibly antifertility role of Aerva lanata in dams' pups.

Multi-Mechanistic and Therapeutic Exploration of Nephroprotective Effect of Traditional Ayurvedic Polyherbal Formulation Using In Silico, In Vitro and In Vivo Approaches

Based on traditional therapeutic claims, NEERI KFT (a traditional Ayurvedic polyherbal preparation) has been innovatively developed in recent time on the decades of experience for treating kidney dysfunction. Due to the lack of scientific evidence, the present investigations are needed to support the rationale use of NEERI KFT. Considering the facts, the study investigated the nephroprotective effect of NEERI KFT against kidney dysfunction using in silico, in vitro and in vivo approaches. In this study, phytochemical and network pharmacology studies were performed for the developed formulation to evaluate the molecular mechanism of NEERI KFT in the amelioration of kidney disease. In vitro nephroprotective and antioxidant effect of NEERI KFT was determined on HEK 293 cells against cisplatin-induced cytotoxicity and oxidative stress. In vivo nephroprotective effect of NEERI KFT was determined against cisplatin-induced nephrotoxicity in Wistar rats, via assessing biochemical markers, antioxidant enzymes and inflammatory cytokines such as TNF-α, IL-1β, CASP-3, etc. The results showed that the compounds such as gallic acid, caffeic acid and ferulic acid are the major constituents of NEERI KFT, while network pharmacology analysis indicated a strong interaction between polyphenols and several genes (CASPs, ILs, AGTR1, AKT, ACE2, SOD1, etc.) involved in the pathophysiology of kidney disease. In vivo studies showed a significant (p < 0.05) ameliorative effect on biochemical markers and antioxidant enzymes (SOD, CAT, GSH, etc.), and regulates inflammatory cytokine (TNF-α, IL-1β, CASP-3) expression in kidney tissue. Hence, it can be concluded that NEERI KFT subsequently alleviates renal dysfunction mediated by cisplatin via attenuating oxidative and inflammatory stress, thus preserving the normalcy of kidney function.

Antidiabetic Activity of Mung Bean or Vigna radiata (L.) Wilczek Seeds in Alloxan-Induced Diabetic Mice

Introduction

Despite the development of oral hypoglycemic medications, diabetes and its associated complications continue to be significant clinical issues. The purpose of this study was to examine the antidiabetic effects of Vigna radiata (L.) Wilczek seeds in mice that had been given alloxan to cause diabetes.

Methods

In Swiss albino mice, diabetes was brought on by a single intraperitoneal injection of the drug alloxan (150 mg/kg). For 14 days, glibenclamide (5 mg/kg) and methanol extract of V. radiata seeds (100, 200, and 400 mg/kg) were given orally. Following oral administration of V. radiata to mice, the blood glucose levels (BGL) and body weight were measured at 7 and 14 days. The mice were sacrificed at the end of the trial, and blood samples were taken for the evaluation of insulin, glycated hemoglobin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), high-density lipoprotein (HDL), total cholesterol (TC), and triglyceride (TG) levels. It was determined how much glycogen was present in the liver. Additionally, the total phenolic and flavonoid contents of V. radiata were determined, along with the in vitro DPPH (2, 2 diphenyl-1-picrylhrazyl) free radical-scavenging activity. P < 0.05 was chosen as the cutoff for statistical significance.

Results

Following oral administration of V. radiata for 14 days, diabetic mice's BGL and bad cholesterol (TC and TG) levels significantly decreased, while HDL levels increased. Treatment with V. radiata significantly decreased the levels of AST, ALT, and glycated hemoglobin when compared with diabetes control. On the other hand, it raised insulin levels and the amount of liver glycogen. V. radiata underwent phytochemical analysis, which identified the presence of tannins, saponins, phenols, alkaloids, terpenoids, steroids, flavonoids, and glycosides. Per gram of V. radiata seed extract, the total phenolic content was 43.12 ± 3.14 mg of gallic acid equivalents, while the total flavonoid content was 38.35 ± 2.6 mg of quercetin equivalents. Ascorbic acid was shown to have an IC₅₀ value of 18.64 µg/ml during a DPPH-scavenging assay, while V. radiata had an IC₅₀ value of 73.35 µg/ml.

Conclusion

According to the findings of the current study, the methanolic extract of the seeds from the plant V. radiata possesses significant antidiabetic characteristics that are on par with those of the commonly used drug glibenclamide. Hence, V. radiata seems to be effective as a natural antidiabetic.

Antidiabetic and antioxidant potential of total extract and supernatant fraction of the roots of Anogeissus leiocarpus in HFD-fed and Streptozocin -induced diabetic rats

The aim of this study was to evaluate the antidiabetic properties of hydro alcoholic extract and supernatant fraction of the roots of Anogeissus leiocarpus, a plant used by traditional healers to treat Diabetes mellitus. Diabetes mellitus was induced by a single intraperitoneal administration of Streptozocin to Sprague Dawley rats under a fructose-enriched fat diet. Diabetic rats were treated with 500 mg/kg of total extract and 100 mg/kg of supernatant. The antidiabetic activity was assessed by measuring blood glucose level, lipid profile, insulin and biochemical parameters together with the antioxidant potential. The administration of total extract and supernatant exhibited significant decrease (p < 0.01) of the blood glucose level in the diabetic rats after 7 days of treatment compared to the diabetic rats. A significant reduction in the serum concentrations of cholesterol (19.7 %) and triglycerides (56.7 %) was observed in the treated diabetic rats. The levels of insulin did not differ across all the groups. However, compared to diabetic rats, HOMA-IR (Homeostasis Model Assessment for Insulin-resistance) and HOMA-β (Homeostasis Model Assessment for β cell function) showed a statistical decrease in insulin resistance and an increase in pancreatic β cell function in the treated diabetic rats. Moreover, total extract and supernatant significantly increased GSH level and decreased lipid peroxidation because of their antioxidant properties. In comparison, the supernatant fraction exerted stronger antidiabetic and antioxidant effects than the total extract. Hence, the roots of Anogeissus leiocarpus are a potent antidiabetic agent that can be developed as an alternative medicine for diabetes and its complications.

Bioprospecting for Anti-COVID-19 Interventions From African Medicinal Plants: A Review

The emergence of the novel coronavirus (SARS-CoV-2) that emanated from Wuhan in China in 2019 has become a global concern. The current situation warrants ethnomedicinal drug discovery and development for delivery of phytomedicines with potential for the treatment of COVID-19. The aim of this review is to provide a detailed evaluation of available information on plant species used in African traditional medicines with antiviral, anti-inflammatory, immunomodulatory, and COVID-19 symptoms relieving effects. Literature from scientific databases such as Scopus, PubMed, Google scholar, African Journals OnLine (AJOL), Science Direct, and Web of Science were used for this review. A total of 35 of the 38 reviewed plants demonstrated a wide range of antiviral activities. Bryophyllum pinnatum, Aframomum melegueta, Garcinia kola, Sphenocentrum jollyanum, Adansonia digitata, Sutherlandia frutescens, Hibiscus sabdariffa, Moringa oleifera, and Nigella sativa possess a combination of antiviral, immunomodulatory, anti-inflammatory, and COVID-19 symptoms relieving activities. Nine, 13, and 10 of the plants representing 23.7%, 34.2%, and 26.3% of the plants studied had antiviral activity with 3 other activities, antiviral activity with 2 other activities, and antiviral with one pharmacological activity alone, respectively. The plants studied were reported to be relatively safe at the subchronic toxicity level, except for 2. The study provides baseline information on the pharmacological activities, toxicity, and chemical components of 9 African medicinal plants with antiviral, immunomodulatory, anti-inflammatory, and symptoms relieving activities, thereby making the plants candidates for further investigation for effectiveness against COVID-19.

Four new cycloartane-type triterpenoids from the leaves of Combretum mellifluum Eichler: assessment of their antioxidant and antileishmanial activities

The beneficial pharmacological actions including antioxidant effects as an antileishmanial, antibacterial, antifungal, antidiabetic, anti-inflammatory, antitumor, antiviral, and analgesic of compounds isolated from Combretum mellifluum Eichler (Combretaceae) are well established. The aim of the present study was to determine the phytochemistry as well as assess the antioxidant and antileishmanial activities of the leaves from Combretum mellifluum Eichler (Combretaceae). Analysis of ethanolic extract resulted in isolation and identification of two epimeric mixtures of four previously unknown cycloartane-type triterpenoids, methyl quadrangularate M and methyl 24-epiquadrangularate M, and 2α,3β,24β-trihydroxy-cycloart-25-ene and 2α, 3β, 24α-trihydroxy-cycloart-25-ene, and eight known compounds. Their structures were using one-dimensional nuclear magnetic resonance (1D NMR), 2D NMR and high-resolution electrospray ionization mass spectroscopy (HRESIMS) analysis. Further, the extract and fractions were tested for antioxidant potential. The ethyl acetate and aqueous fractions demonstrated the highest antioxidant activity against 2,2-dipheny-1-picrylhydrazl (DPPH) free radicals, which correlated directly with total flavonoid content. All extracts and fractions from C. mellifluum Eichler were assessed for antileishmanial activity. The supernatant fraction exhibited highest potential, inhibiting the growth of Leishmania amazonensis with IC₅₀ value 31.29 μg/ml. Our findings provide information on the chemical composition of C. mellifluum and the potential beneficial therapeutic usefulness as an antioxidant agent in various diseases.

Ethnopharmacological evaluation of antioxidant, anti-angiogenic, and anti-inflammatory activity of some traditional medicinal plants used for treatment of cancer in Togo/Africa

ETHNOPHARMACOLOGICAL RELEVANCE

Cancer is a multistep disease and its management is exceedingly expensive. Nowadays medicinal plants are gaining more attention in drug discovery and approximately 70% of anticancer drugs were developed from natural products or plants. A strong candidate from medicinal plant with anticancer potential should have four major properties: antioxidant, anti-inflammatory, anti-angiogenic, and cytotoxic activities.

AIM OF THE STUDY

In order to assess Togolese traditional healer's claims about the anticancer potential of medicinal plants and obtain candidate plants for anticancer drug discovery, some species were selected from surveys and evaluated for their antioxidant, anti-inflammatory, anti-angiogenic and cytotoxic activities.

METHODS

Four species, Cochlospermum planchonii (CP), Piliostigma thonningii (PT), Paullinia pinnata (PP), and Securidaca longipedunculata (SL) were selected and analyzed to detect the phytochemical components. The mentioned bioactivities were evaluated using in vitro, ex vivo and in vivo assays.

RESULTS

Relative to SL extract, CP and PT have shown significantly high polyphenols and flavonoids content. The DPPH, FRAP, and TAC of the extracts revealed that CP, PT, and PP have a potent antioxidant effect compared to SL. MDA analysis revealed the same antioxidant activity as CP, PT and PP showed a minor MDA level. The egg albumin denaturation assay showed that IC50 of CP and PP was significantly higher than control (P < 0.05). In contrast, the Bovine Serum Albumin (BSA) results showed a nonsignificant effect (P > 0.05). Notably, SL extract was nonsignificant to control in both Egg Albumin and BSA. Furthermore, angiogenesis assay showed that SL at 50 μg/ml and PP at 100 μg/ml effectively reduced the number of blood vessels than control and showed a potent anti-angiogenic effect (2.7-fold and 2.5-fold, respectively, P < 0.05). No cytotoxicity on PBMC was reported for CP, PP, and PT up to 1000 μg/ml, whereas SL at 1000 μg/ml exhibit benign cytotoxicity (P < 0.0001).

CONCLUSION

This study provided in vitro evidence supporting further evaluation on cancer cell lines and tumors in vivo.

Acute and repeated dose 60-day oral toxicity assessment of chemically characterized Berberis hispanica Boiss. and Reut in Wistar rats

Berberis hispanica Boiss. & Reut (B. hispanica) belongs to the family Berberidaceae, which is currently used in traditional medicines. This article aimed to study the phytochemical composition and acute and subacute toxicity of B. hispanica extract in rats. The phytochemical composition of B. hispanica extract was characterized using GC-MS. The acute toxicity was investigated in vivo via the oral administration of single doses including 400, 800, 1,000, 1,200, and 1,400 mg/kg for 14 days. The subchronic toxicity was studied through oral administration of 400 mg/kg for 60 days. The findings of the phytochemical analysis of B. hispanica extract showed the presence of various phytochemical compounds. Acute toxicity results revealed serious clinical symptoms and mortalities in rats treated with 800 mg/kg up to a maximum of 1,400 mg/kg. With acute toxicity, subchronic toxicity results showed also serious signs of toxicity including biochemical and histological alterations in animals treated with 1,400 mg/kg. B. hispanica extract revealed to be toxic in rats orally treated under both subacute (>400 mg/kg) and subchronic toxicity conditions (400 mg/kg). The outcome of this study serves the society as it provides toxicological evidence of B. hispanica used in alternative medicines

Safety assessment of ethanolic root extract of Zaleya decandra (EEZD) in Wistar rats

Zaleya decandra is a prostrate, glabrous, succulent herb of the family Aizoaceae. In recent years the pharmacological efficacy of the plant such as the hepatoprotective, antimicrobial, antidiabetic, anti-inflammatory and anticancer activities has been reported. However, a long-term toxicity study of Z. decandra is yet to be carried out. In the present study, the acute dose of 2000 mg/kg b.w. of ethanolic extract of Z. decandra (EEZD) administered orally to Wistar rats gained gradual weight with time and appeared healthy without any record of mortality. In the sub-chronic toxicity study, the rats showed no remarkable increase or decrease in their weight even at the highest dose of 500 mg/kg b.w. The haematological, biochemistry and serum marker enzyme parameters did not show any dose dependent change in the values. Further, the histology micrographs confirmed that the tissue architecture of all the vital organs were not affected by EEZD treatment. Hence, the EEZD (500 mg/kg b.w.) is considered safe for a 90-day period. Therefore, the present study warrants extensive investigation of EEZD using higher pre-clinical model system to substantiate the findings. The GC-MS analysis revealed the presence of 39 phytoconstituents including octadecenoic acid, hexadecanoic and phytosterols such as campesterol, sitosterol and stigmasterol.

Nephroprotective effect of Combretum micranthum G. Don in nicotinamide-streptozotocin induced diabetic nephropathy in rats: In-vivo and in-silico experiments

ETHNOPHARMACOLOGICAL RELEVANCE

Combretum micranthum G. Don (CM) is extensively used in traditional medicine throughout West Africa and commonly known as "long-life herbal tea" or "plant to heal". Further, traditional healers frequently use the title plant to mitigate of renal disorders.

AIM OF THE STUDY

To explore the nephroprotective property of standardised hydroalcoholic extract of Combretum micranthum in nicotinamide-streptozotocin induced diabetic nephropathy in rats. In addition, in-silico computational experiments were performed with bioactive compounds of the title plant against PPARα and PPARγ.

MATERIAL AND METHODS

Male rats were made diabetic by a single intraperitoneal (ip) injection of STZ (50 mg/kg), 15 min after ip administration of NA (100 mg/kg) dissolved in normal saline. The diabetic rats received CM extract (200 and 400 mg/kg p.o.) daily, for eight weeks. Body weights and blood glucose (non-fasting and fasting) of rats were measured weekly. Daily food and water consumption were also measured. After 8 weeks of treatment, urine biochemical parameters such as N-Acetyl-β-D-Glucosaminidase (NAG), urea (UR), uric acid (UA), creatinine (CRE), and serum markers of diabetes, kidney damage and liver damage such as insulin, lipid parameters), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (γGT), albumin (Alb), magnesium (Mg²⁺), calcium (Ca²⁺), phosphorus (P), were estimated. Blood glycosylated hemoglobin (HbA1_C) were also estimated. kidney and liver were used for biochemical estimation of oxidative stress markers such as lipid peroxidation, superoxide dismutase (SOD) activity and glutathione peroxidase (GPx) activity. The kidney and pancreas were used for histopathological study. Further, HPLC chemoprofiling of CM extract and in-silico molecular simulation experiments were performed.

RESULTS

At the end of eight weeks, renal damage induced by the consequence of prolong diabetic condition was confirmed by altered levels of serum and urine kidney and liver function markers, oxidative stress markers and histopathological variations in kidney. Treatment with CM extract ameliorated the diabetes mellitus-induced renal biochemical parameters and histopathological changes. Further, HPLC-UV & MS experiments revealed that CM extract contains several bioactive compounds including hyperozide (62.35 μg/mg of extract) and quercitrin (19.07 μg/mg of extract). In-silico experiment exhibited cianidanol (-17.133), epicatechin (-15.107) exhibited higher docking score against PPARα and luteoforol (-11.038), epigallocatechin (-10.736) against PPARγ. Based on docking and drug likeness score, four bioactive compounds were selected for molecular dynamic experiments. Cianidanol and epigallocatechin out of the 30 compounds are concluded as a potential candidate for the treatment of DN through activating PPARα and PPARγ target protein.

CONCLUSIONS

Taken together, the present study provided the scientific footage for the traditional use of Combretum micranthum.

Hypertension treatment with Combretum micranthum or Hibiscus sabdariffa, as decoction or tablet: a randomized clinical trial

Hibiscus sabdariffa L. (local names: bissap, karkade) and Combretum micranthum (kinkeliba) are widely known in traditional medicines and popular beliefs for their antihypertensive effect. This study assessed the clinical effectiveness of these two plants in the galenic forms of tablet and brew (decoction) in noncomplicated hypertensive patients. In total, 219 hypertensive patients with systolic blood pressure (SBP) between 140 and 180 mmHg and/or diastolic blood pressure (DBP) between 90 and 110 mmHg, without cardiovascular or renal complications, were involved in a multicentric randomized clinical trial in Senegal comparing five treatment regimens: bissap tablets (2 × 375 mg/day), bissap brew (10 g of calyx/day), kinkeliba tablets (2 × 200 mg/day), kinkeliba brew (10 g of leaves/day), and captopril (2 × 50 mg/day) as control. During the 6 months' follow-up, a significant and equivalent decrease of SBP was observed with the herbal drug approach (-19.5 ± 16.1 mmHg, p < 0.001) and control group (-19.7 ± 16.7, p < 0.001). Regarding the galenic forms, the brews tended to be slightly more effective than tablets (reduction of SBP: -20.7 ± 15.1 mmHg vs -18.7 ± 16.7). The rates of clinically significant effectiveness (decrease in SBP ≥ 10 mmHg) were 75%, 67%, and 65% with bissap, kinkeliba, and captopril, respectively. After 6 months, target blood pressure of <140/90 mmHg was attained by 49% of patients with bissap, 51% with kinkeliba and 40% with captopril. Bissap and kinkeliba appeared, at doses utilized, to be as effective as captopril over the 6 months' follow-up. In subsequent studies, brews might be started with a lower dosage.

Parameter Optimization and Potential Bioactivity Evaluation of a Betulin Extract from White Birch Bark

Owing to its pharmacological potential, betulin has attracted substantial attention in the past two decades. The present work attempts to extract betulin from Betula platyphylla Suk. bark by the ultrasonic-assisted ethanol method and to evaluate its potential bioactivities. The critical process variables affecting the yield were optimized by a four-factor, three-level, central composite response surface methodology (RSM). A betulin yield of 92.67% was achieved under the optimum conditions: 65% ethanol concentration, 1:25 ratio of white birch bark to solvent, an extraction temperature of 30 °C, and an extraction time of 30 min. The ratio of solid to solvent is the most significant parameter in terms of yield. The optimal conditions were validated through experiments, and the observed value (92.67 ± 2.3%) was interrelated with the predicted value (92.86 ± 1.5%). The betulin extract was analyzed quantitatively by HPLC and quantitatively by LC/MS, before its potential biological activities were evaluated. Bioactivity surveys confirmed that the betulin extract showed not only no embryo deformity through zebrafish administration experiments, but also no cytotoxicity through MTT assays. Furthermore, the betulin extract had strong antioxidant activities in vitro by scavenging ferric reducing power (FRAP), 1,1-diphenyl-2-picryl hydrazyl(DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and chelating metal ions. This study demonstrates that ultrasonic-assisted ethanol extraction may be a green, efficient method for the extraction of betulin from white birch bark, and that betulin extracts are potentially useful in cosmetics, food supplements, or pharmaceutical applications.

Acute and subchronic oral toxicity assessments of Combretum micranthum (Combretaceae) in Wistar rats

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Acute and subchronic oral toxicity assessments of Combretum micranthum leaves extract were evaluated in Wistar rats of both sexes.

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In acute oral toxicity assessment, LD50 of Combretum micranthum leaves extract is greater than 5000 mg/kg.

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In subchronic oral toxicity assessment at doses of 500 and 1000 mg/kg/day for 28 days, No significant changes in food consumption, body weight gain, organ weights and in biochemical parameters.

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The level of PLT increased in female rats in the sub-chronic study but the immune system was not affected.

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No treatment related pathology was identified during histopathology.

Background

Combretum micranthum (CM) (Combretaceae) is widely used in traditional medicine throughout West Africa for the treatment of diabetes, hypertension, inflammation, malaria and liver ailments. In our recent research we demonstrated that CM has nephroprotective potentials in diabetes mellitus, hypertension and renal disorders. However, to the best of our knowledge, no systematic study concerning its toxicity profile has been reported.

Aim of the study

The study carried out to evaluates the potential toxicity of the hydroalcoholic extract from leaves of the CM, through the method of acute and sub-chronic oral administration in rats.

Materials and methods

During the acute toxicity study, male and female rats were orally administrated with CM extract at single doses of 5000 mg/kg (n = 5/group/sex). Abnormal behaviour, toxic symptoms, weight, and death were observed for 14 consecutive days to assess the acute toxicity. For sub-chronic toxicity study, the extract was administered orally at doses of 500 and 1000 mg/kg (n = 5/group/sex) daily to Wistar rats for 28 days. The general behaviour and body weight of the rats was observed daily. A biochemical, haematological, macroscopical and histopathological examinations of several organs were conducted at the end of the treatment period. The CM extract was subjected to Fourier transform infrared spectrophotometric examination in order to detect the presence or absence of cyanide toxic compounds.

Results

The absence of absorbance peaks between the 2220−2260 cm⁻¹ region of FT-IR spectrum of CM, indicating the absence of cyanide groups. This suggested that the CM extract may not contain toxic substances. During the acute toxicity test, no mortality or adverse effects were noted at the dose of 5000 mg/kg. In the subchronic study, the CM extract induced no mortality or treatment-related adverse effects with regard to body weight, general behaviour, relative organ weights, hematological, and biochemical parameters. Histopathological examination of vital organs showed normal architecture suggesting no morphological alterations.

Conclusion

The present study revealed that oral administration of CM extract for 28 days, at dosage up to 1000 mg/kg did not induce toxicological damage in rats. From acute toxicity study, the median lethal dose (LD₅₀) of the extract was estimated to be more than 5000 mg/kg.

Nephroprotective activity of Combretum micranthum G. Don in cisplatin induced nephrotoxicity in rats: In-vitro, in-vivo and in-silico experiments

Nephrotoxicity is known to be a major complication during cisplatin chemotherapy in cancer patients. In the present study, the protective effect of a hydroalcoholic extract of Combretum micranthum (CM) against cisplatin (CP)-induced renal damage was evaluated using in-vitro human embryonic kidney (HEK)-293 cells and in-vivo experiments. Further, in-silico molecular docking and dynamic experiments were carried out with bioactive compounds of the title plant against nuclear factor kappa B (NF-κB) and soluble epoxide hydrolase (sEH). Incubation of HEK-293 cells with cisplatin resulted in a significant increase in cell death with changes in normal cellular morphology. Co-treatment of HEK-293 cells with CP and CM extract at varying concentrations resulted in significant enhancement of cell growth compared to CP treatment indicating the cytoprotective activity of CM with an EC₅₀ 8.136 μg/mL. In vivo nephroprotective activity was evaluated by administering CM (200 and 400 mg/kg, p.o) to rats for 10 days followed by single intraperitonial injection of CP (7.5 mg/kg) on the 5th day of the experiment. Nephrotoxicity induced by CP was apparent by elevated levels of serum and urine kidney function markers, transaminases, oxidative stress markers and histopathological alterations in kidney. Pre-treatment with CM normalized the renal function at both the doses by ameliorating the CP-induced renal damage markers, oxidative stress and histopathological variations. In-silico studies showed that, out of the thirty bioactive compounds, isovitexin and gallic acid exhibited a higher docking score of -22.467, -21.167 kcal/mol against NF-κB. Cianidanol and epicatechin exhibited a higher docking score of -14.234, -14.209 kcal/mol against sEH. The protective effect of CM extract in CP-induced nephrotoxicity might be attributed to its antioxidant, anti-inflammatory activity by inhibiting NF-κB and sEH upregulation.