Medicinal plants with concomitant anti-diabetic and anti-hypertensive effects as potential sources of dual acting therapies against diabetes and hypertension: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes and hypertension are pathophysiologically related diseases that co-exist with a wider complex of metabolic diseases having similar set of risk factors. There are numerous ethnopharmacological evidences on the anti-diabetic and/or anti-hypertensive properties of medicinal plants from various parts of the world, which are used as therapies to concomitantly manage diabetes and hypertension.

AIM OF THE REVIEW

This article reviewed findings on medicinal plants with both anti-diabetic and anti-hypertensive effects reported in same experimental study to facilitate the development of dual-acting therapies against diabetes and hypertension.

MATERIALS AND METHODS

A literature search was carried out on different scientific search engines including, but not limited to "PubMed", "Google Scholar", "Scopus" and ScienceDirect to identify published data in which plants in same experimental studies were reported to possess both anti-hyperglycemic and anti-hypertensive effects. Subsequently, the anti-diabetic/anti-hypertensive potency ratio (ψ) of the medicinal plants was computed.

RESULTS

Sixty-four studies with 102 plant species matched the selection criteria. Members of the Fabaceae family were the most investigated plants, while the ψ greatly varied across the plants, with only 11 plants having a ψ ≃ 1. Withania somnifera Dunal was the only plant reported to show blood glucose-lowering and diuretic effects in humans, comparable to daonil. Caffeic acid, chlorogenic acid, caftaric acid, cichoric acid, verbascoside, leucosceptoside A, isoacteoside, fucoxanthin and nicotinamide were the reported dual acting anti-diabetic and anti-hypertensive compounds identified and/or isolated in the plants.

CONCLUSIONS

This review suggests that medicinal plants possess varied therapeutic dynamics against hypertension and diabetes that could be exploited for the discovery of therapeutic preparation(s) or agent(s) for treating the two diseases.

Vanillin and vanillic acid modulate antioxidant defense system via amelioration of metabolic complications linked to Fe2+-induced brain tissues damage

The therapeutic effect of phenolics on neurodegenerative diseases has been attributed to their potent antioxidant properties. In the present study, the neuroprotective activities of vanillin and vanillic acid were investigated in Fe²⁺- induced oxidative toxicity in brain tissues by investigating their therapeutic effects on oxidative imbalance, cholinergic and nucleotide-hydrolyzing enzymes activities, dysregulated metabolic pathways. Their cytotoxicity was investigated in hippocampal neuronal cell lines (HT22). The reduced glutathione level, SOD and catalase activities were ameliorated in tissues treated with the phenolics, with concomitant depletion of malondialdehyde and nitric oxide levels. They inhibited acetylcholinesterase and butyrylcholinesterase activities, while concomitantly elevated ATPase activity. Treatment with vanillin led to restoration of oxidative-depleted metabolites and reactivation of the pentose phosphate and purine metabolism pathways, with concomitant activation of pathways for histidine and selenoamino metabolisms. While vanillic acid restored and reactivated oxidative-depleted metabolites and pathways but did not activate any additional pathway. Both phenolics portrayed good binding affinity for catalase, with vanillic acid having the higher binding energy of -7.0 kcal/mol. Both phenolics were not cytotoxic on HT22 cells, and their toxicity class were predicted to be 4. Only vanillin was predicted to be permeable across the blood brain barrier (BBB). These results insinuate that vanillin and vanillic acid confer a neuroprotective effect on oxidative brain damage, when vanillin being the most potent.

Chemical and functional properties of cassava starch, durum wheat semolina flour, and their blends

High-quality cassava starch (HQCS) produced from high-yielding low-cyanide improved cassava variety, TMS 30572, was mixed with durum wheat semolina (DWS) on a replacement basis to produce flour samples containing 0, 20, 30, 50, 70, and 100% cassava starch. They were analyzed for chemical composition (proximate, amylose, free sugars, starch, wet gluten, and cyanide) and functional properties (pasting, swelling power, solubility, water absorption, water binding, starch damage, diastatic and α-amylase activity, dough mixing, and stability). Protein, carbohydrate, fat, and ash of flour samples ranged from 0.75-12.31%, 70.87-87.80%, 0.95-4.41%, and 0.12-0.83%, respectively. Cyanide levels in all the flour samples were less than 0.1 ppm. Amylose content varied between 19.49% for cassava and 28.19% for wheat, correlating significantly with protein (r = 0.95, P = 0.004) and ash contents (r = 0.92, P = 0.01) at 5%. DWS and HQCS had similar pasting temperatures (50.2-53°C), while other pasting properties increased with increasing levels of HQCS. Dough mixing stability of samples decreased with increasing levels of HQCS. All the flour samples had α-amylase activity greater than 200. Both HQCS and DWS compare favorably well in swelling power (7.80-9.01%); but the solubility of wheat starch doubled that of cassava. Starch damage varied between 3.3 and 7.2 AACC for semolina and starch, with the latter having higher absorption rate (97%), and the former, higher absorption speed (67 sec). Results obtained showed positive insight into cassava-wheat blend characteristics. Data thus generated provide additional opportunities of exploiting cassava utilization and hence boost its value-addition potentials for product development.

Suppressive Effects of Clerodendrum volubile P Beauv. [Labiatae] Methanolic Extract and Its Fractions on Type 2 Diabetes and Its Complications

Type 2 diabetes is the most prominent of all diabetes types, contributing to global morbidity and mortality. Availability and cost of treatment with little or no side effect especially in developing countries, remains a huge burden. This has led to the search of affordable alternative therapies especially from medicinal plants. In this study, the antidiabetic effect of the methanolic extract, dichloromethane (DCM), butanol (BuOH) and aqueous fractions of Clerodendrum volubile leaves were investigated in type 2 diabetic rats for their effect on glucose homeostasis, serum insulin level and hepatic biomarkers, lipid profile, pancreatic redox balance and Ca2+ levels, and β-cell distribution and function. The DCM was further fractionated to isolate the active compounds, biochanin and 5,7,4'-trimethoxykaempferol. They were investigated for their toxicity and ADMET properties, α-glucosidase and angiotensin I converting enzyme (ACE) inhibitory activities in silico. There were significant (p < 0.05) decrease in blood glucose, cholesterol, LDL-C, vLDL-C, triglyceride, AST and ALT levels in all treated groups, with DCM fraction showing the best activity. All treated rats showed significantly (p < 0.05) improved anti-oxidative activities. Treatment with the DCM fraction led to significant (p < 0.05) increased serum insulin and pancreatic Ca2+ levels, as well as improved β-cell distribution and function. DCM fraction also showed improved glucose tolerance. DCM fraction dose-dependently inhibited ACE activity. The toxicity class of the isolated compounds was predicted to be 5. They were also predicted to be potent inhibitors of cytochrome P (CYPs) 1A2, 2D6 and 3A4. They docked well with α-glucosidase and ACE. These results indicate the therapeutic potential of the plant against type 2 diabetes, with the DCM fraction being the most potent which may be attributed to the isolated flavones. It further suggests antihypertensive potentials of the DCM fraction. However, inhibition of CYPs by the flavones may suggest caution in usage with other prescribed drugs metabolized by these enzymes.

Caffeic Acid Protects against Iron-Induced Cardiotoxicity by Suppressing Angiotensin-Converting Enzyme Activity and Modulating Lipid Spectrum, Gluconeogenesis and Nucleotide Hydrolyzing Enzyme Activities

The protective effects of caffeic acid on angiotensin-converting enzyme (ACE) and purinergic enzyme activities, as well as gluconeogenesis was investigated in iron-induced cardiotoxicity. Cardiotoxicity was induced in heart tissues harvested from healthy male SD rats by 0.1 mM FeSO₄. Treatment was carried out by co-incubating hearts tissues with caffeic acid and 0.1 mM FeSO₄. Cardiotoxicity induction significantly (p < 0.05) depleted GSH level, SOD, catalase, and ENTPDase activities, with concomitant elevation of the levels of malondialdehyde (MDA), nitric oxide, ACE, ATPase, glycogen phosphorylase, glucose 6-phosphatase, fructose 6-biphsophatase, and lipase activities. There was significant (p < 0.05) reversion in these levels and activities on treatment with caffeic acid. Caffeic acid also caused depletion in cardiac levels of cholesterol, triglyceride, LDL-c, while elevating HDL-c level. Our results suggest the protective effect of caffeic acid against iron-mediated cardiotoxicity as indicated by its ability to suppress oxidative imbalance and ACE activity, while concomitantly modulating nucleotide hydrolysis and metabolic switch.

Vernonia Amygdalina Del. stimulated glucose uptake in brain tissues enhances antioxidative activities; and modulates functional chemistry and dysregulated metabolic pathways

Brain glucose uptake is usually reduced in type 2 diabetes owing to downregulation of brain glucose transporters. The ability of Vernonia amygdalina to stimulate glucose uptake as well as ameliorate glucose-induced oxidative stress and proinflammation were investigated in rat brain. Hot infusion of V. amygdalina leaves was incubated with rat brain tissues for 2 h in the presence of glucose. Another incubation with glucose only, served as negative control while metformin served as positive control. Incubation of brain tissues with V. amygdalina led to significant (p < 0.05) increase in glucose uptake, reduced glutathione, nitric oxide and non-thiol proteins levels, superoxide dismutase, catalase and ATPase activities, while concomitantly decrease in myeloperoxidase activity and malondialdehyde level compared to the negative control. Incubation with glucose only, led to the development of nitrate, amide II and amide I functional groups which were removed on incubation with the infusion. LC-MS analysis revealed depletion of oxidative stress-induced 2-keto-glutaramic acid and cysteinyl-tyrosine metabolites in brain tissues, with concomitant generation of S-formylglutathione and adenosine tetraphosphate by the infusion. Pathway analysis of the metabolites revealed an activation of pyruvate metabolism pathway in the negative control, with the infusion reducing the intensity fold. LC-MS analysis of the infusion revealed the presence of l-serine, l-cysteine, l-proline, nicotinic acid, cumidine, salicylic acid, isoquinoline, 3-methyl-, and γ-octalactone. Except for l-serine, l-cysteine and l-proline, the other compounds were predicted to be permeable across the blood brain barrier. These results indicate the brain glucose uptake stimulatory and neuroprotective effect of V. amygdalina.

Chemical evaluation of African palm weevil, Rhychophorus phoenicis, larvae as a food source

The chemical properties of the African palm weevil, Rhychophorus phoenicis (F.) (Coleoptera: Curculionidae), larvae were evaluated using standard methodology. The chloroform-methanol extract yielded 37.12% on a dry basis. The oil was liquid at room temperature with a flash point of 36.0 °C. Analysis of the physical constants indicated values of 192.25 Wijs and 427.70 mg KOH/g as iodine and saponification, respectively. Fatty acid analysis of the extracted oil showed the presence of unsaturated fatty acids at low levels. Palmitic acid and stearic acid constituted 35.3 and 60.5% of the oil, respectively. The usual behaviour of the oil at room temperature, irrespective of the level of unsaturation of its constituent fatty acid was noted. The total protein content of the defatted palm weevil larva (dry basis) was estimated at 66.3%. The amino acid values compared favourably to FAO reference protein, except for tryptophan, which was limiting. All the other essential amino acids were adequate. Mineral analysis revealed high levels of potassium (1025 mg/100 g) and phosphorus (685 mg/100 g). The dried and defatted palm weevil lava represents a very good source of protein, and a good complement of essential amino acids.

Molecular mechanism of antiproliferation potential of Acacia honey on NCI-H460 cell line

Lung cancer is one of the leading causes of death worldwide. We investigated the molecular mechanism of antiproliferation potential of Acacia honey on NCI-H460 cells by cell cycle, viability, cytokines, calcium ion and gene expression analysis. Acacia honey inhibited cells proliferation, arrested G0/G1 phase, stimulated cytokines, calcium ion release as well as suppressed p53 and Bcl-2 expression in a dose-dependent manner. We proposed that the molecular mechanism of the antiproliferation potential of Acacia honey on NCI-H460 cell line is due to cell cycle arrest, stimulation of cytokines and calcium ion as well as downregulation of Bcl-2 and p53 genes.

Type 2 diabetes induced oxidative brain injury involves altered cerebellar neuronal integrity and elemental distribution, and exacerbated Nrf2 expression: therapeutic potential of raffia palm (Raphia hookeri) wine

Neurodegenerative diseases, such as Alzheimer's disease have been recognized as one of the microvascular complications of type 2 diabetes (T2D). In this study, the effect of T2D on neuronal integrity and elemental distribution in the cerebellar cortex, as well as the therapeutic effect of Raffia Palm (Raphia hookeri) wine (RPW) were investigated in male albino rats. T2D was induced in 4 groups of rats using fructose and streptozotocin. One group served as negative control which was administered water, the second and third group were administered 150 and 300 mg/kg bodyweight of RPW, while the fourth was administered metformin (200 mg/kg bodyweight). Two other groups of normal rats were administered distilled water (control) and of RPW (300 mg/kg bodyweight). The rats were sacrificed after 5 weeks of treatment, and brains were collected. The cerebellum was removed, and several parts analyzed by immunochemistry, histology and scanning electron microscopy (SEM). Remaining brain tissues were used to analyze for the oxidative stress biomarkers and acetylcholinesterase activity. These analyses revealed oxidative damage with concomitantly increased acetylcholinesterase activity and upregulation of Nrf2 expression in the diabetic brain cerebellar cortexes. Histological and microscopic analysis also revealed altered distribution of neurons and axonal nodes with concomitant elevated levels of several heavy metals. Treatment with RPW significantly elevated glutathione (GSH) level, superoxide dismutase (SOD) and catalase activities, as well as depleted acetylcholinesterase and malondialdehyde (MDA) level and concomitantly inhibited Nrf2 expression. It also improved neuronal integrity and reduced the levels of heavy metals in brain. Taken together, the results of this study suggest that the RPW may afford a novel neuroprotective potential against diabetic neurodegeneration.

Raffia palm (Raphia hookeri G. Mann & H. Wendl) wine modulates glucose homeostasis by enhancing insulin secretion and inhibiting redox imbalance in a rat model of diabetes induced by high fructose diet and streptozotocin

ETHNOPHARMACOLOGICAL RELEVANCE

Raffia palm (Raphia hookeri) wine (RPW) is amongst the natural products from plants, utilized singly or in combination with other medicinal plants for the treatment of several ailments including Diabetes Mellitus (DM). However, there is a scientific dearth on its antidiabetic activity.

AIM

The antidiabetic effect of RPW and its possible mechanism of actions were investigated in diabetic rats.

METHODS

Four groups of male SD rats were first supplied with 10% fructose solution ad libitum for 2 weeks instead of drinking water followed by an intraperitonial injection of streptozotocin (40 mg/kg) to induce diabetes. Two diabetic groups were administered RPW at 150 and 300 mg/kg bodyweight (BW) respectively; a group was administered with metformin, while the other one was served as a negative control. Two groups of normal rats were administered with water and RPW (300 mg/kg BW) and served as normal control and normal toxicology group, respectively.

RESULTS

Five weeks treatment of RPW led to significant (p < 0.05) increase in serum insulin and HDL-c levels with concomitant reduction in blood glucose, fructosamine, ALT, uric acid, triglycerides and LDL-c levels in diabetic rats. Rats treated with RPW had elevated levels of GSH, SOD, catalase, ATPase and α-amylase activities, while reduced NO level and myeloperoxidase activity was observed in their serum and pancreatic tissues. RPW also improved pancreatic β-cell function and restored β- and acinar cells morphology, and capillary networks. The activities of glycogen phosphorylase, fructose 1,6 biphosphatase, glucose-6-phosphatase, and acetylcholinesterase were also inhibited in RPW-treated diabetic rats, with concomitant down regulation of Nrf2 gene expression.

CONCLUSION

The data of this study suggest that RPW modulates glucose homeostasis by enhancing insulin secretion as well as inhibiting redox imbalance in diabetic rats, which may be attributed to the synergetic effects of its phytochemical constituents as identified by GC-MS analysis.

Hyperglycemia-induced oxidative brain injury: Therapeutic effects of Cola nitida infusion against redox imbalance, cerebellar neuronal insults, and upregulated Nrf2 expression in type 2 diabetic rats

The therapeutic effect of the hot water infusion of Cola nitida against hyperglycemia-induced neurotoxicity, cerebellar neurodegeneration and elemental deregulations was investigated in fructose-streptozotocin induced rat model of type 2 diabetes (T2D). A diabetic group was administered drinking water, two other diabetic groups were treated with C. nitida at 150 and 300 mg/kg bodyweight respectively, while another group was administered metformin (200 mg/kg bodyweight). Two other groups consisting of normal rats, were administered drinking water and C. nitida (300 mg/kg bodyweight). After 6 weeks of treatment, their brains were collected. Treatment with C. nitida led to suppression of oxidative stress, significantly elevating reduced glutathione (GSH) levels, superoxide dismutase and catalase activities, concomitant with depletion of malondialdehyde (MDA) levels. Acetylcholinesterase and ATPase activities were significantly inhibited in C. nitida-treated diabetic rats. Histological and microscopic analysis also revealed a restorative effect of C. nitida on T2D-altered distribution of elements, neurons and axonal nodes. Treatment with C. nitida also led to significant inhibition of Nrf2 expression in the cerebellar cortex. These results suggest the therapeutic effects of C. nitida in maintenance of the neuronal integrity and antioxidant status of the brain in T2D. These neuroprotective activities can be attributed to the identified alkaloid, caffeine in the infusion.

Pectolinarigenin from the leaves of Clerodendrum volubile shows potent immunomodulatory activity by inhibiting T - cell proliferation and modulating respiratory oxidative burst in phagocytes

There have been increasing interest in the use of plant-derived substance as immunomodulators for the treatment and management of inflammatory ailments. Clerodendrum volubile, a leafy vegetable is known for its folkloric applications in the treatments of several inflammatory related ailments, but with little scientific evidence. This study reports the isolation, structure elucidation and in vitro immunomodulatory potentials of pectolinarigenin from C. volubile leaves. The immunomodulatory potentials of the crude methanolic extract and fractions [n-hexane (Hex), dichloromethane (DCM), ethyl acetate (EtOAc) and n - butanol (BuOH)] were investigated on whole blood, neutrophil and macrophage phagocytic respiratory burst using luminol-amplified chemiluminescence technique. DCM fraction showed higher inhibitory activity on respiratory burst, indicating high suppressive immunomodulatory potency. The DCM fraction was further fractionated using a gravity column chromatography loaded with silica gel. The column was eluted with mixtures of Hex and DCM (92.5:7.5) in increasing order of polarity up to Hex: DCM (88:12) to afford 5,7-Dihydroxy-6,4'-dimethoxyflavone (pectolinarigenin). The structure of the compound was established using data obtained from ¹H- and ¹³C NMR spectroscopies and mass spectrometry. The isolated flavone was investigated for its inhibitory activity of neutrophil phagocytes respiratory burst as well as T - Cell proliferation. The compound exhibited significant activities (at p <0.05) indicating high suppressive immunomodulatory potency. The potent suppressive effect of pectolinarigenin on polymorphonuclear neutrophils (PMNs) respiratory oxidative burst and T - cell proliferation suggests an immunomodulatory potential and pathway of the flavonoid.

Dietary Fatty Acids from Leaves of Clerodendrum Volubile Induce Cell Cycle Arrest, Downregulate Matrix Metalloproteinase-9 Expression, and Modulate Redox Status in Human Breast Cancer

The antiproliferative effect of the fatty acid components of Clerodendrum volubile leaves as well as its antioxidant effect on MCF-7 and MDA-MB-231 human breast cancer cell lines were investigated. Fatty acids extracted from C. volubile leaf oil were subjected to gas chromatography mass spectrometry (GCMS) analysis. The cells were cultured and treated with the fatty acids for 48 h, after which the antiproliferation effect was ascertained via MTT assay and cell viability analysis using BD fluorescence activated cells sorting (FACS) Calibur. Cell cycle was analyzed by flow cytometry on FACS Calibur. Western blotting was used in determining expression of proteins in the cell lines. The treated cell lines were assessed for reduced glutathione level, catalase, superoxide dismutase, and lipid peroxidation. The fatty acids significantly inhibited cell proliferation, arrested G0/G1 phase, downregulated the expression of MMP-9, and attenuated oxidative stress in of MCF-7 cell lines but had little or no effect on MDA-MB-231 cell lines. These results indicate the therapeutic potential of the fatty acids components of the leaves of C. volubile on human breast cancer, which may be explored further in drug development.

Bambara-wheat composite flour: rheological behavior of dough and functionality in bread

The rheological behavior and functional properties of doughs from bambara–wheat composite flour was investigated. Bambara–wheat composite flour was prepared by substituting wheat with 0%, 10%, 15%, and 20% of bambara flour. The rheological behavior of their dough was analyzed with Mixolab. Breads produced from the flour were analyzed for physical characteristics. Organoleptic analysis was carried out by 20 panelists. Mixolab analysis revealed, except for stability time, depreciating values for dough consistency (C1), protein weakening (C2), starch gelatinization (C3), amylase activity (C4), and retrogradation (C5) as the inclusion of bambara flour increased. Physical characteristics of the loaves revealed significant (P < 0.05) decreasing bread volume and increasing specific volume, respectively, as bambara inclusion increased. There was significant (P < 0.05) difference between wheat bread and the bambara–wheat composites in all the studied quality attributes. 15% bambara–wheat composite bread was the most accepted amongst the composite breads. Inclusion of bambara flour improved the protein behavior of the composite, but did not evidently show benefits in the baking characteristics.

The antidiabetic properties of the hot water extract of kola nut (Cola nitida (Vent.) Schott & Endl.) in type 2 diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Cola nitida is amongst the evergreen plants native to West Africa used in the treatment of various ailments including diabetes.

AIM OF THE STUDY

This study aims to investigate the antidiabetic effects of the hot water extract of C. nitida seeds in type 2 diabetic rats.

METHODS

Type 2 diabetic rats were orally administered with low (150 mg/kg bw) and high (300 mg/kg bw) doses of the hot water extract for 6 wk and thereafter, blood glucose, insulin level, lipid profile, pancreatic β-cell function, perfusion and morphology, redox imbalance, glycolytic and cholinergic enzymes, as well as of caspase-3 and Nrf2 expressions were measured.

RESULTS

Treatment with the extract led to significant depletion of blood glucose, serum triglycerides, LDL-cholesterol, fructosamine, ALT, and uric acids, while elevating serum insulin and HDL-cholesterol levels. The infusion also significantly (p < 0.05) elevated GSH level, SOD, catalase, α-amylase, and ATPase activities, with concomitant depletion of myeloperoxidase enzyme activity, and NO and MDA levels in the serum and pancreas. Significantly (p < 0.05) improved pancreatic β-cell function and morphology were observed in rats treated with C. nitida, with restored pancreatic capillary networks. C. nitida inhibited the activities of glycogen phosphorylase, fructose 1,6 biphosphatase, glucose 6 phosphatase, and acetylcholinesterase while downregulated the Nrf2 expression. NMR analysis of the extract revealed the presence of caffeine and theobromine. The molecular docking studies indicated that identified compounds displayed strong molecular interactions with caspase-3 and Nrf2.

CONCLUSION

These results insinuate the antidiabetic activities of C. nitida hot water extract and may be attributed to the NMR-identified compounds.

Raffia palm (Raphia hookeri) wine extenuates redox imbalance and modulates activities of glycolytic and cholinergic enzymes in hyperglycemia-induced testicular injury in type 2 diabetic rats

This study investigated the effects of Raffia palm wine (RPW) on redox imbalance, glycolytic and cholinergic enzymes, and ATPase activities in hyperglycemia-induced oxidative testicular injury. Type 2 diabetes (T2D) was induced in male albino rats (Sprague-Dawley) by first administering 10% fructose solution for 14 days, before injecting with an intraperitoneal injection (40 mg/kg body weight) of streptozotocin. Raffia palm wine was administered to two diabetic groups at 150 and 300 mg/kg body weight (bw), when untreated diabetic group was used as a negative control, and metformin-fed group was served as a positive control. The rats were sacrificed after 5 weeks of treatment, and testes were harvested. Treatment with RPW led to lower levels of nitric oxide, malondialdehyde and myeloperoxidase activity, with concomitant elevation of reduced glutathione level, superoxide dismutase, catalase and ATPase activities. Raffia palm wine also inhibited glycogen phosphorylase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and acetylcholinesterase, while restoring the altered testicular morphology to near-normal. The results of this study suggest the therapeutic potentials of RPW against the effects of T2D on testicular functions and morphology. PRACTICAL APPLICATIONS: Diabetes mellitus is one of the fastest growing global epidemy, with most developing countries being at the receiving end owing to the cost of treatment. Testicular damage has been recognized as one of the complications of diabetes, and if left untreated will lead to erectile dysfunction followed by infertility. Raffia palm wine is among the common natural beverage in West Africa, which is utilized for both social and medicinal purposes. In this study, for the first time we showed its ability to protect diabetes-induced testicular injury in type 2 diabetic rats. This may be of great benefit in managing diabetes associated erectly dysfunction and male infertility, as Raffia palm wine is readily available in all seasons. This study will also improve the medicinal use of this wine, which may also indirectly improve its commercial benefit.

Dacryodes edulis (G. Don) H.J. Lam modulates glucose metabolism, cholinergic activities and Nrf2 expression, while suppressing oxidative stress and dyslipidemia in diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Dacryodes edulis L. is an evergreen tree indigenous to western and eastern Africa which is utilized for nutritional and medicinal purposes. Folklorically, different parts of the tree are used in treating and managing diabetes and its complications.

AIMS

The antidiabetic effect of the butanol fraction of D. edulis ethanol extract (BFDE) was studied in fructose-streptozotocin induced type 2 diabetic rats.

METHODS

The ethanol extract was fractionated to yield the hexane, dichloromethane, ethyl acetate, butanol and aqueous fractions. The in vitro antidiabetic activities of the fractions were determined by their ability to inhibit α-glucosidase activity. BDFE was the most active and showed no cytotoxic effect while stimulating glucose uptake in 3T3-L1 adipocytes. Thus, selected for in vivo study. Diabetic rats were grouped into 4. The negative control group was administered water only, another group was treated with metformin (200 mg/kg bodyweight), while the other groups were administered BDFE at 150 and 300 mg/kg bodyweight respectively. Two other groups consisting of normal rats were given water and BFDE (300 mg/kg bodyweight) respectively, with the former serving as normal control. After 6 weeks of intervention, the rats were humanely sacrificed using appropriate anaesthesia.

RESULTS

Treatment with the fraction significantly (p < 0.05) reduced the blood glucose level of the diabetic rats, with concomitant increase in serum insulin secretion. It also caused significant (p < 0.05) elevation of reduced glutathione level, superoxide dismutase, catalase, α-amylase, and ATPase activities, with concomitant depletion in myeloperoxidase activity, NO and MDA levels of the serum and pancreas. The pancreatic morphology and β-cell function were significantly improved in BFDE-treated rats, with restoration of the pancreatic capillary networks. Treatment with BFDE significantly (p < 0.05) inhibited the activities of glycogen phosphorylase, fructose 1,6 biphosphatase, glucose 6 phosphatase, and acetylcholinesterase, while suppressing the expression of Nrf2. HPLC analysis revealed the presence of gallic acid, vanillic acid, vanillin, and (-)-epicatechin in the fraction.

CONCLUSION

These results portray the antidiabetic and antioxidative properties of BFDE, which may be a synergistic consequence of the identified phenolics.

Potential biological activity of acacia honey

Recent advances in functional foods-based research have increasingly become an area of major interest because it affects human health and activities. Functional foods are classes of foods with health promoting and disease preventing properties in addition to multiple nutritional values and of such type is honey. Acacia honey is a type of honey produced by bees (Apis mellifera) fed on Acacia flowers, hence the name. This review focuses on the potential biological activities of Acacia honey which includes quality, antioxidant, immuno-modulatory, antiproliferative and neurological properties at in vitro and in vivo levels. Based on our review, Acacia honey used from various researches is of high purity, contains some bioactive compounds ranging from vitamins, phenolics, flavonoids and fatty acids. It's highly nutritional with strong antioxidant and immuno-modulatory potentials which may therefore be considered a potential candidate for both cancer prevention and treatment. Neurologically, it may be considered as a viable therapeutic agent in the management of Alzheimer's disease.

Histochemistry, phenolic content, antioxidant, and anti-diabetic activities of Vernonia amygdalina leaf extract

Vernonia amygdalina leaves were investigated for their histochemical properties and antidiabetic activities. Histochemical analysis of the leaf revealed distributions of acidic lipid, mucilage, and pectin, lipids, polyphenols, and alkaloids at the mid rib, glandular trichome, and epidermis. HPLC analysis of the leaves hot water infusion revealed the presence of quercetin and (-)-epi-catechin. The infusion had significant (p < 0.05) 2,2'-diphenyl-1-picrylhydrazyl scavenging activity and ferric reducing antioxidant power. Ex vivo antioxidative analysis revealed the ability of the infusion to increase glutathione level, superoxide dismutase, and catalase activities, while concomitantly depleting malondialdehyde level and DNA fragmentation in Fe²⁺ -induced hepatic injury. The infusion showed significant (p < 0.05) inhibitory activity against α-glucosidase and pancreatic lipase. It also inhibited intestinal glucose absorption and enhanced muscle glucose uptake, respectively. The ability of the infusion to abate oxidative stress, DNA fragmentation and stimulate muscle glucose uptake may suggest the antioxidative, anti-apoptotic, and insulin-sensitizing activity of V. amygdalina. PRACTICAL APPLICATIONS: Vernonia amygdalina (bitter leaf) is among the common leafy vegetables in West Africa reported for its various medicinal and nutritional properties. It is utilized as a food ingredient as well as supplement for the treatment and management of type 2 diabetes (T2D). Its ability to inhibit intestinal glucose absorption, enhance muscle glucose uptake, and protect against hepatic oxidative stress gives more credence to its reported antidiabetic properties. Being a common leafy vegetable, V. amygdalina can be a cheap source of nutraceutical for the treatment and management of T2D and its complications.

Short-Term Feeding of Fibre-Enriched Biscuits: Protective Effect against Hepatotoxicity in Diabetic Rats

The effects of fibre-enriched biscuit on biomarkers associated with hepatotoxicity in diabetic rats were investigated. Diabetes was induced by single intraperitoneal injection of alloxan monohydrate. Treatment lasted for 14 days after which the rats were sacrificed by cervical dislocation. Blood serum was analyzed to determine hepatic function enzymes. The liver was also analyzed to determine hepatic lipid profile and antioxidant enzymes. Induction of diabetes led to elevated levels of ALP, AST, and ALT. These were, however, significantly (p < 0.05) reduced in the fibre-enriched biscuit fed (treated) group. There was no significant difference in the serum bilirubin and total protein levels of the studied groups. Reduced albumin level was observed in the diabetic group; this was further lowered on feeding with fibre-enriched biscuits. Induction of diabetes led to increased hepatic level of cholesterol, triglyceride (TG), low density lipoprotein (LDL), and lipid peroxidation and decreased activities of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) and HDL level. These were significantly (p < 0.05) reversed on feeding with fibre-enriched biscuit. This study portrays the protective effect of fibre-enriched biscuit on increased oxidative stress and hyperlipidemia in hepatic tissues of alloxan-induced diabetic rats.

Fatty Acids Rich Extract From Clerodendrum volubile Suppresses Cell Migration; Abates Oxidative Stress; and Regulates Cell Cycle Progression in Glioblastoma Multiforme (U87 MG) Cells

Glioblastoma multiforme (GBM) is a malignant primary type of brain cancer with high proliferation and metastasis rates due to involvement of the microglial cell. It is resistant against available chemotherapy. Many strategic protocols have been developed but prognosis and patient life has not improved substantially. In this study, the anti-metastatic and antioxidant effect of fatty acids from Clerodendrum volubile leaves were investigated in U87-MG (Human Glioblastoma Multiforme) cell lines. The extracted fatty acids were incubated with U87-MG cells for 48 h. The anti-proliferative effect was determined by MTT assay, while apoptosis and cell cycle were analyzed with BD FACSCalibur. The transwell assay protocol was utilized in the analysis of cell migration and invasion. The treated cell lines were also assessed for reduced glutathione (GSH) level, catalase, superoxide dismutase (SOD) and lipid peroxidation. The fatty acid extract showed significant inhibitory activity on cell proliferation and cell cycle progression, mitigated oxidative stress, and suppressed migration and invasion in U-87 MG cell lines. These results give credence to the therapeutic potential of this plant against cancer, especially GBM.