The effects of berberine on reactive oxygen species production in human neutrophils and in cell-free assays

Neuroprotective Agents with Therapeutic Potential for COVID-19

COVID-19 patients can exhibit a wide range of clinical manifestations affecting various organs and systems. Neurological symptoms have been reported in COVID-19 patients, both during the acute phase of the illness and in cases of long-term COVID. Moderate symptoms include ageusia, anosmia, altered mental status, and cognitive impairment, and in more severe cases can manifest as ischemic cerebrovascular disease and encephalitis. In this narrative review, we delve into the reported neurological symptoms associated with COVID-19, as well as the underlying mechanisms contributing to them. These mechanisms include direct damage to neurons, inflammation, oxidative stress, and protein misfolding. We further investigate the potential of small molecules from natural products to offer neuroprotection in models of neurodegenerative diseases. Through our analysis, we discovered that flavonoids, alkaloids, terpenoids, and other natural compounds exhibit neuroprotective effects by modulating signaling pathways known to be impacted by COVID-19. Some of these compounds also directly target SARS-CoV-2 viral replication. Therefore, molecules of natural origin show promise as potential agents to prevent or mitigate nervous system damage in COVID-19 patients. Further research and the evaluation of different stages of the disease are warranted to explore their potential benefits.

Antioxidants: an approach for restricting oxidative stress induced neurodegeneration in Alzheimer's disease

Alzheimer's disease (AD) is the leading cause of dementia, affecting millions of people worldwide. Oxidative stress contributes towards induction of neurodegeneration. It is one of the reasons behind initiation and progression of Alzheimer's disease. Understanding of oxidative balance and restoration of oxidative stress has demonstrated its effectiveness in the management of AD. Various natural and synthetic molecules have been found to be effective in different models of AD. Some clinical studies also support the use of antioxidants for prevention of neurodegeneration in AD. In this review we are summarizing the development of antioxidants to restrict oxidative stress induced neurodegeneration in AD.

Evaluation of Berberine as an Adjunct to TB Treatment

Tuberculosis (TB) is the global health problem with the second highest number of deaths from a communicable disease after COVID-19. Although TB is curable, poor health infrastructure, long and grueling TB treatments have led to the spread of TB pandemic with alarmingly increasing multidrug-resistant (MDR)-TB prevalence. Alternative host modulating therapies can be employed to improve TB drug efficacies or dampen the exaggerated inflammatory responses to improve lung function. Here, we investigated the adjunct therapy of natural immune-modulatory compound berberine in C57BL/6 mouse model of pulmonary TB. Berberine treatment did not affect Mtb growth in axenic cultures; however, it showed increased bacterial killing in primary murine bone marrow-derived macrophages and human monocyte-derived macrophages. Ad libitum berberine administration was beneficial to the host in combination with rifampicin and isoniazid. Berberine adjunctive treatment resulted in decreased lung pathology with no additive or synergistic effects on bacterial burdens in mice. Lung immune cell flow cytometry analysis showed that adjunctive berberine treatment decreased neutrophil, CD11b+ dendritic cell and recruited interstitial macrophage numbers. Late onset of adjunctive berberine treatment resulted in a similar phenotype with consistently reduced numbers of neutrophils both in lungs and the spleen. Together, our results suggest that berberine can be supplemented as an immunomodulatory agent depending on the disease stage and inflammatory status of the host.

Effects of berberine on cholinesterases and monoamine oxidase activities, and antioxidant status in the brain of streptozotocin (STZ)-induced diabetic rats

OBJECTIVES

Several studies had been conducted to examine the link between diabetes and diabetes encephalopathy. This study was conducted to examine the potency of berberine (BER) on the restoration of impaired neurochemicals in the brain of streptozotocin (STZ)-induced diabetic Wistar rats.

METHODS

Fifty-six (56) adult rats weighing between 200 and 230 g were randomly divided into seven groups (n=8) as follows; Group I is normal control; Groups II and III were normal rats treated with 50 and 100 mg/kg respectively; Group IV-VII were STZ-induced rats, but Groups V-VII were treated with acarbose (25 mg/kg), 50 and 100 mg/kg of BER, respectively.

RESULTS

The result of the study showed that untreated STZ-induced diabetic rats have increased acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase (MAO) activities, and malonylaldehyde (MDA) level, with concomitant decrease of superoxide dismutase (SOD), glutathione peroxidase (GPx) activities, and glutathione (GSH) level. However, daily treatment with 50 and 100 mg/kg BER and ACA significantly reversed these effects.

CONCLUSIONS

The findings of this study clearly indicated that BER possesses neuro-protective and antioxidative potentials and normalize neurochemical impairment distort by diabetes.

Berberine mitigates oxidative damage associated with testicular impairment following mercury chloride intoxication

In this study, we assessed the protective effect of berberine (BBR) against mercuric chloride (HgCl₂)-induced reproductive impairment. Twenty-eight adult male Wistar albino rats were placed into four equal groups: control, BBR, HgCl₂, and BBR + HgCl₂. All the treatments were orally administered for seven consecutive days. The rats exposed to HgCl₂ showed a marked decrease in testosterone accompanied by an increase in lipid peroxidation (LPO) and nitric oxide (NO). Additionally, HgCl₂ decreased glutathione (GSH) content, deactivated catalase (CAT) and glutathione reductase (GR), and suppressed the activities and mRNA expression of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in the testicular tissue. In addition, histological deformations and testicular cell loss were recorded, as evidenced by the upregulation of caspase-3 following HgCl₂ intoxication. Notably, BBR administration reversed the testicular impairments associated with HgCl₂ exposure. These findings suggest that BBR protected the testicular tissue following HgCl₂ exposure through inhibiting the disturbance in the testosterone level and enhanced the antioxidant capacity. PRACTICAL APPLICATIONS: Heavy metals are naturally existing metallic elements in the earth's crust. These trace metals have the potential to cause multiple adverse reactions to the living systems, even at low exposure doses. Human exposure may also result from industrial, agricultural, and domestic activities. Berberine (BBR, a naturally occurring quaternary benzylisoquinoline alkaloid) is a protoberberine and is the representative main active ingredient in all parts of Berberis species. BBR has been used widely in folk medicine worldwide for its multiple pharmacological and therapeutic activities; for example, in the treatment of digestive and reproductive system disorders, microorganism infections, hemorrhage and wound healing, and cardiovascular and ophthalmic diseases. We found that BBR administration was able to abrogate significantly the reproductive toxicity associated with Hg intoxication. This protective effect comes from its strong antioxidant, anti-inflammatory, and antiapoptotic activities; suggesting that BBR may be applied to alleviate reproductive toxicity associated with Hg intoxication.

Diallyl Disulfide Suppresses Inflammatory and Oxidative Machineries following Carrageenan Injection-Induced Paw Edema in Mice

Diallyl disulfide (DADS) is the major organosulfur constituent in garlic, with a variety of pharmacological activities including antioxidant and anti-inflammatory. Here, we examined the potential antiedematous impact of DADS- versus carrageenan-mediated paw edema in mice. Carrageenan injection potentiated an inflammatory reaction as presented by the elevated serological C-reactive protein (CRP) levels and transcription of tumor necrosis factor-alpha (TNF-α, Tnfα), interleukin-1 beta (IL-1β, Il1b), interleukin-2 (IL-2, Il2), inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase-2 (COX-2, Ptgs2), prostaglandin E2 (PGE2), monocyte chemoattractant protein-1 (MCP-1, Ccl1), nuclear factor kappa B (NF-κB), and myeloperoxidase (MPO) activity, while interleukin-10 (IL-10) was declined in the injured paw tissue. Additionally, carrageenan elevated lipid peroxidation in terms of malondialdehyde (MDA) and decreased glutathione content (GSH). Remarkably, DADS was found to inhibit the inflammatory signaling, suppressed the developed oxidative damage, and protected the histopathological alterations in the inflamed paw tissue in response to carrageenan injection. Our findings suggest that DADS could be used as an alternative therapy used to alleviate the pathophysiological changes associated with the genesis of paw edema through its potent anti-inflammatory and antioxidant impacts.