Induction of rat hepatic mitochondrial membrane permeability transition pore opening by leaf extract of Olax subscorpioidea

Olax subscorpioidea prevented scopolamine-induced memory impairment through the prevention of oxido-inflammatory damage and modulation of cholinergic transmission

ETHNOPHARMACOLOGICAL RELEVANCE

Olax subscorpioidea oliv. is a shrub plant of the Olacaceae family with reported usage in ethnomedicine as a nootropic agent for the management of Alzheimer's-like dementia.

AIM

The aim of this study is to investigate the nootropic potential of methanol extract of Olax subscorpioidea (MEOS) in scopolamine-induced Alzheimer's-like dementia.

MATERIALS AND METHODS

Thirty male mice, assigned into six groups (n = 8), were used for this study. Group, I received distilled water, group II received scopolamine (1 mg/kg, i.p.), groups iii-v received 25, 50, and 100 mg/kg, p.o. of MEOS and scopolamine (1 mg/kg/i.p.), and group vi received donepezil 5 mg/kg, p.o.and scopolamine (1 mg/kg, i.p.). The animals were pre-treated with MEOS and Donepezil for 14 days, and scopolamine from the 8th to 14th day. Followed by cognitive, oxidative stress, neuroinflammation, and histology assessments.

RESULTS

100 mg/kg MEOS significantly reduced transfer latency and increased discrimination index in the elevated plus maze and novel object recognition test cognitive assessments. 100 mg/kg MEOS, significantly reduced oxidative stress, protect endogenous antioxidants, suppressed neuroinflammation, and acetylcholinesterase (ACHE) activity. The histomorphometry study of the hippocampus revealed that MEOS prevented extensive pyknosis, karyolysis, chromatolysis, and loss of hippocampal neurons that accompanied scopolamine treatment.

CONCLUSION

MEOS protected against Alzheimer's-like dementia via the suppression of neuroinflammation and oxidative stress associated with scopolamine-induced amnesic behavior.

Jatonik polyherbal mixture induced rat liver MMPT pore opening in normal Wistar rat: In vitro and in vivo studies

Objective

To assess acute toxicity, the in vitro and in vivo effects of methanol and ethyl acetate extracts (JME and JEE) of Jatonik polyherbal mixture on some mitochondria-related parameters and their effect on the activity of some liver enzymes.

Methods

Acute toxicity of JME and JEE was determined using Lorke's method. In vitro and in vivo opening of the mitochondrial membrane permeability transition pore (MMPT pore) was spectrophotometrically assayed. Production of malondialdehyde (MDA) as an index of lipid peroxidation and the activity of mitochondrial ATPase was evaluated in vitro and in vivo and the effect of JME and JEE on the activity of liver enzymes such as alkaline phosphatase (ALP), aspartate and alanine aminotransferase (AST and ALT) and gamma-glutamyl transferase (GGT) was also investigated.

Results

JME had an LD50 of 3 808 mg/kg b.w whereas JEE had an LD50 greater than 5 000 mg/kg b.w. of rats. After the rats have been fed with both extracts, a photomicrograph of a piece of liver tissue showed no apparent symptoms of toxicity. From the in vitro and in vivo studies, both extracts prompted intact mitochondria to open their MMPT pores. When compared to the control, lipid peroxide product release and ATPase activity were significantly increased (P < 0.05) in vitro and in vivo. The activities of AST, ALT, and GGT were all reduced at 50 mg/kg when treated with JME, but the activity of AST was considerably enhanced when treated with JEE (P < 0.05). The results revealed that both JME and JEE of the Jatonik polyherbal mixture had low toxicity, profound MMPTpore induction, and enhanced ATPase activity, but an increased MDA production.

Conclusion

Jatonik extracts may be a promising target for drug development in diseases where there is dysregulation of apoptosis, however, further studies are needed to better clarify the molecular mechanism involved in these phenomena.

Ethnopharmacological uses, phytochemistry, pharmacology, and toxicology of Olax subscorpioidea Oliv (Olacaceae): a review

Background

The plant Olax subscorpioidea Oliv (Olacaceae) is a shrub that is widely available in Africa. It has been used in traditional medicine to treat various diseases including asthma, pain, inflammation, gastrointestinal and central nervous system (CNS) disorders, cough, diabetes mellitus, cancer, infectious diseases, hepatic diseases, and many other diseases. Several phytochemical and pharmacological investigations were conducted on this plant. However, comprehensive information on this medicinally important plant is not available in the literature. Therefore, in this review, we aimed to provide comprehensive and critical information on all the reported ethnomedicinal uses, phytochemistry, pharmacological activities, and potential toxicity of Olax subscorpioidea to highlight its therapeutic potentials based on traditional usage and identify research gaps as a basis for further investigations to develop novel therapeutic compounds.

Main body

The available information about the plant was retrieved from the online bibliographic databases (PubMed and Google Scholar) and published PhD dissertation using the search terms Olax subscorpioidea, traditional uses, ethnomedicinal uses, phytochemistry, pharmacology, toxicology, and safety. Phytochemical studies have shown that the plant contains several bioactive compounds such as rutin, morin, quercetin, caffeic acid, santalbic acid, n-hexadecanoic acid, squalene, nonacosane, hentriacontane, and many more compounds. Also, pharmacological investigations revealed that Olax subscorpioidea has antidepressant, antiepileptic, anti-Alzheimer’s, cytotoxic, antioxidant, antihyperlipidemic, analgesic, antiinflammatory, antiarthritic, antidiabetic, anticancer, antiulcer, antimicrobial, hepatoprotective, apoptotic, antiprotease, and other CNS effects.

Conclusion

Several pharmacological studies on Olax subscorpioidea have established its ethnopharmacological uses. However, there are limited phytochemical and pharmacological studies to validate other folkloric claims of the plant. Therefore, extensive phytochemical and further pre-clinical efficacy and safety evaluations to fully establish its therapeutic potentials and elucidate its mechanisms of pharmacological actions could be necessary.

Graphical abstract

Kigelia africana (Lam.) Benth leaf extract inhibits rat brain and liver mitochondrial membrane permeability transition pore opening

The effect of Kigelia africana on mitochondrial membrane permeability transition has not been explored. In this study, the effect of a solvent fraction of Kigelia africana leaf extract on mitochondrial membrane permeability transition of rat brain and liver was evaluated. A methanol extract of K. africana leaves was fractionated into different solvents by vacuum liquid chromatography and following preliminary screening, the dichloromethane:ethylacetate (1:1) fraction was selected for further assays. Constituent phytochemicals in the fraction were revealed by thin-layer chromatography and further purification was carried out to characterize the compounds. Brain and liver mitochondria were isolated and used for mitochondrial membrane permeability transition and adenosine triphosphatase assays. Exogenous Ca²⁺ and Al³⁺ were used to trigger the mitochondrial membrane permeability transition opening. Physicochemical properties revealed by thin-layer chromatography showed that the isolated compounds were flavonoids. The extract inhibited mitochondrial membrane permeability transition opening in the presence and absence of triggering agents in brain and liver mitochondria. It also inhibited mitochondrial lipid peroxidation and adenosine triphosphatase activity. These results suggest that the extract can limit the rate of apoptosis via inhibition of mitochondrial membrane permeability transition which is pivotal to the mitochondrial apoptotic pathway and is an important therapeutic target in some pathological conditions.

Phytochemical, Antioxidant and Mitochondrial Permeability Transition Studies on Fruit-Skin Ethanol Extract of Annona muricata

Uncontrolled cell proliferation hallmarks cancer and most cancer cells have developed multiple resistance to the drugs employed for their treatment. The study examined the phytochemical and antioxidant properties of the fruit-skin ethanol extract of Annona muricata Linn. (ESA) and its effect on rat liver mitochondrial membrane permeability transition (MMPT). Qualitative phytochemical study and antioxidant assays were carried out following established protocols while the opening of the MMPT pore in the presence of varying concentrations of the extract was assayed spectrophotometrically under succinate-energized conditions. Calcium chloride (CaCl₂) and spermine were used to trigger and inhibit pore opening respectively. Cytochrome c release was assayed for using ELISA kit. Terpenoids, steroids, phenols among other phytochemicals were found present in ESA and the extract showed very low antioxidant properties at the tested concentrations based on the diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity assay. Lipid peroxidation was induced in a concentration-dependent manner on both the cytosolic and mitochondrial hepatocyte fractions in vitro. In the absence of CaCl₂ 0.84 mg/mL concentration of ESA induced MMPT pore opening by 129% while the extracts showed no inhibitory activity in its presence. The induction fold corresponded with the concentrations of cytochrome c released. The fruit-skin ethanol extract of Annona muricata at certain concentrations may possibly contain bioactive compounds that induce apoptosis.

HPLC-DAD finger printing, antioxidant, cholinesterase, and α-glucosidase inhibitory potentials of a novel plant Olax nana

BACKGROUND

The medicinal importance of a novel plant Olax nana Wall. ex Benth. (family: Olacaceae) was revealed for the first time via HPLC-DAD finger printing, qualitative phytochemical analysis, antioxidant, cholinesterase, and α-glucosidase inhibitory assays.

METHODS

The crude methanolic extract of O. nana (ON-Cr) was subjected to qualitative phytochemical analysis and HPLC-DAD finger printing. The antioxidant potential of ON-Cr was assessed via 1,1-diphenyl,2-picrylhydrazyl (DPPH), 2,2-azinobis[3-ethylbenzthiazoline]-6-sulfonic acid (ABTS) and hydrogen peroxide (H2O2) free radical scavenging assays. Furthermore, acetylcholinesterase (AChE) & butyrylcholinesterase (BChE) inhibitory activities were performed using Ellman's assay, while α- glucosidase inhibitory assay was carried out using a standard protocol.

RESULTS

The qualitative phytochemical analysis of ON-Cr revealed the presence of secondary metabolites like alkaloids, flavonoids, tannins, sterols, saponins and terpenoids. The HPLC-DAD finger printing revealed the presence of 40 potential compounds in ON-Cr. Considerable anti-radical activities was revealed by ON-Cr in the DPPH, ABTS and H2O2 free radical scavenging assays with IC50 values of 71.46, 72.55 and 92.33 μg/mL, respectively. Furthermore, ON-Cr showed potent AChE and BChE inhibitory potentials as indicated by their IC50 values of 33.2 and 55.36 μg/mL, respectively. In the α-glucosidase inhibition assay, ON-Cr exhibited moderate inhibitory propensity with an IC50 value of 639.89 μg/mL.

CONCLUSIONS

This study investigated Olax nana for the first time for detailed qualitative phytochemical tests, HPLC-DAD finger printing analysis, antioxidant, anticholinesterase and α-glucosidase inhibition assays. The antioxidant and cholinesterase inhibitory results were considerable and can provide scientific basis for further studies on the neuroprotective and anti-Alzheimer's potentials of this plant. ON-Cr may further be subjected to fractionation and polarity guided fractionation to narrow down the search for isolation of bioactive compounds.