Effects of Gnaphalium affine Extract on the Gel Properties of •OH-Induced Oxidation of Myofibrillar Proteins

This study aimed to investigate the effect of Gnaphalium affine extract (GAE) (0.04, 0.2 and 1 mg/g protein) on the gel properties of porcine myofibrillar proteins (MPs) in a simulated Fenton oxidation system, using tea polyphenols (TPs) at similar concentrations of 0.04, 0.2, and 1 mg/g protein, respectively, as a contrast. The findings revealed that as the TP concentration increased, the water retention of MP gels decreased significantly (p < 0.05). In contrast, MP gels containing medium and high concentrations of GAE exhibited significantly higher water retention than those with low concentrations of GAE (p < 0.05). When the concentration of GAE was increased to 1 mg/g protein, the strength of MP gels was significantly reduced (p < 0.05) by 33.32% compared with the oxidized control group, suggesting that low and medium GAE concentrations support MP gel formation. A texture profile analysis indicated that an appropriate GAE concentration improved gel structure and texture. Dynamic rheological characterization revealed that low concentrations of TP (0.04 mg/g protein) and low and medium concentrations of GAE (0.04 and 0.2 mg/g protein) strengthened the protein gel system. Conversely, high concentrations of TP and GAE (1.0 mg/g protein) damaged the protein gel system or even promoted the collapse of the gel system. Scanning electron microscopy revealed that higher TP concentrations disrupted the gel, whereas low and medium GAE concentrations maintained a more continuous and complete gel network structure compared with the oxidized control group. This indicates that an appropriate GAE concentration could effectively hinder the destruction of the gel network structure by oxidation. Therefore, based on the obtained results, 0.2 mg/g protein is recommended as the ideal concentration of GAE to be used in actual meat processing to regulate the oxidization and gel properties of meat products.

Development of grape polyphenols as multi-targeting strategies for Alzheimer's disease

Alzheimer's disease (AD) is by far the most prevalent neurodegenerative disease of aging and is a major burden for patients, caregivers, and the overall health care system. The complexity of AD pathophysiology and the lack of deep understanding of disease mechanisms impeded the development of AD therapy. Currently approved treatments for AD only modestly improve cognitive function but do not modify disease course. The lack of pharmacological approaches has led to the consideration of alternative strategies to prevent or to slow down the progression of AD. There has been a growing interest in the scientific community regarding the impact of diet and nutrition on AD. Grape derived nutraceuticals and phytochemical compounds have demonstrated anti-amyloidogenic, antioxidative, anti-inflammatory and neurotrophic properties and present as potential novel strategies for AD treatment. In this review, we summarize promising grape derived polyphenols that have been shown to modulate AD pathophysiology including amyloid plaques and neurofibrillary tangles formation, AD-induced oxidative stress, neuroinflammation and synaptic dysfunction.

Anti-Neuroinflammatory Potential of Polyphenols by Inhibiting NF-κB to Halt Alzheimer's Disease

Alzheimer's disease (AD) is an irrevocable chronic brain disorder featured by neuronal loss, microglial accumulation, and progressive cognitive impairment. The proper pathophysiology of this life-threatening disorder is not completely understood and no exact remedies have been found yet. Over the last few decades, research on AD has mainly highlighted pathomechanisms linked to a couple of the major pathological hallmarks, including extracellular senile plaques made of amyloid-β (Aβ) peptides, and intracellular neurofibrillary tangles (NFTs) made of tau proteins. Aβ can induce apoptosis, trigger an inflammatory response, and inhibit the synaptic plasticity of the hippocampus, which ultimately contributes to reducing cognitive functions and memory impairment. Recently, a third disease hallmark, the neuroinflammatory reaction that is mediated by cerebral innate immune cells, has become a spotlight in the current research area, assured by pre-clinical, clinical, and genetic investigations. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), a cytokine producer, is significantly associated with physiological inflammatory proceedings and thus shows a promising candidate for inflammation- based AD therapy. Recent data reveal that phytochemicals, mainly polyphenol compounds, exhibit potential neuroprotective functions and these may be considered as a vital resource for discovering several drug candidates against AD. Interestingly, phytochemicals can easily interfere with the signaling pathway of NF-κB. This review represents the anti-neuroinflammatory potential of polyphenols as inhibitors of NF-κB to combat AD pathogenesis.

Exploring Potential of Alkaloidal Phytochemicals Targeting Neuroinflammatory Signaling of Alzheimer's Disease

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that is marked by cognitive dysfunctions and the existence of neuropathological hallmarks such as amyloid plaques, and neurofibrillary tangles. It has been observed that a persistent immune response in the brain has appeared as another neuropathological hallmark in AD. The sustained activation of the microglia, the brain's resident macrophages, and other immune cells has been shown to aggravate both tau and amyloid pathology and may consider as a connection in the AD pathogenesis. However, the basic mechanisms that link immune responses in the pathogenesis of AD are unclear until now since the process of neuroinflammation can have either a harmful or favorable effect on AD, according to the phase of the disease. Numerous researches recommend that nutritional fruits, as well as vegetables, possess neurodefensive properties against the detrimental effects of neuroinflammation and aging. Moreover, these effects are controlled by diverse phytochemical compounds that are found in plants and demonstrate anti-inflammatory, neuroprotective, as well as other beneficial actions. In this review, we focus on the link of neuroinflammation in AD as well as highlight the probable mechanisms of alkaloidal phytochemicals to combat the neuroinflammatory aspect of AD.

Circadian and sleep dysfunction in Alzheimer's disease

Alzheimer's disease (AD) is a devastating and irreversible cognitive impairment and the most common type of dementia. Along with progressive cognitive impairment, dysfunction of the circadian rhythms also plays a pivotal role in the progression of AD. A mutual relationship among circadian rhythms, sleep, and AD has been well-recommended. The etiopathogenesis of the disturbances of the circadian system and AD share some general features that also unlock the outlook of observing them as a mutually dependent pathway. Indeed, the burden of amyloid β (Aβ), neurofibrillary tangles (NFTs), neuroinflammation, oxidative stress, and dysfunction of circadian rhythms may lead to AD. Aging can alter both sleep timings and quality that can be strongly disrupted in AD. Increased production of Aβ and reduced Aβ clearance are caused by a close interplay of Aβ, sleep disturbance and raised wakefulness. Besides Aβ, the impact of tau pathology is possibly noteworthy to the sleep deprivation found in AD. Hence, this review is focused on the primary mechanistic complexities linked to disruption of circadian rhythms, sleep deprivation, and AD. Furthermore, this review also highlights the potential therapeutic strategies to abate AD pathogenesis.

Exploring the Promise of Flavonoids to Combat Neuropathic Pain: From Molecular Mechanisms to Therapeutic Implications

Neuropathic pain (NP) is the result of irregular processing in the central or peripheral nervous system, which is generally caused by neuronal injury. The management of NP represents a great challenge owing to its heterogeneous profile and the significant undesirable side effects of the frequently prescribed psychoactive agents, including benzodiazepines (BDZ). Currently, several established drugs including antidepressants, anticonvulsants, topical lidocaine, and opioids are used to treat NP, but they exert a wide range of adverse effects. To reduce the burden of adverse effects, we need to investigate alternative therapeutics for the management of NP. Flavonoids are the most common secondary metabolites of plants used in folkloric medicine as tranquilizers, and have been claimed to have a selective affinity to the BDZ binding site. Several studies in animal models have reported that flavonoids can reduce NP. In this paper, we emphasize the potentiality of flavonoids for the management of NP.

Combination Drug Therapy for the Management of Alzheimer's Disease

Alzheimer's disease (AD) is the leading cause of dementia worldwide. Even though the number of AD patients is rapidly growing, there is no effective treatment for this neurodegenerative disorder. At present, implementation of effective treatment approaches for AD is vital to meet clinical needs. In AD research, priorities concern the development of disease-modifying therapeutic agents to be used in the early phases of AD and the optimization of the symptomatic treatments predominantly dedicated to the more advanced AD stages. Until now, available therapeutic agents for AD treatment only provide symptomatic treatment. Since AD pathogenesis is multifactorial, use of a multimodal therapeutic intervention addressing several molecular targets of AD-related pathological processes seems to be the most practical approach to modify the course of AD progression. It has been demonstrated through numerous studies, that the clinical efficacy of combination therapy (CT) is higher than that of monotherapy. In case of AD, CT is more effective, mostly when started early, at slowing the rate of cognitive impairment. In this review, we have covered the major studies regarding CT to combat AD pathogenesis. Moreover, we have also highlighted the safety, tolerability, and efficacy of CT in the treatment of AD.

Molecular Insight into the Therapeutic Promise of Flavonoids against Alzheimer's Disease

Alzheimer’s disease (AD) is one of the utmost chronic neurodegenerative disorders, which is characterized from a neuropathological point of view by the aggregates of amyloid beta (Aβ) peptides that are deposited as senile plaques and tau proteins which form neurofibrillary tangles (NFTs). Even though advancement has been observed in order to understand AD pathogenesis, currently available therapeutic methods can only deliver modest symptomatic relief. Interestingly, naturally occurring dietary flavonoids have gained substantial attention due to their antioxidative, anti-inflammatory, and anti-amyloidogenic properties as alternative candidates for AD therapy. Experimental proof provides support to the idea that some flavonoids might protect AD by interfering with the production and aggregation of Aβ peptides and/or decreasing the aggregation of tau. Flavonoids have the ability to promote clearance of Aβ peptides and inhibit tau phosphorylation by the mTOR/autophagy signaling pathway. Moreover, due to their cholinesterase inhibitory potential, flavonoids can represent promising symptomatic anti-Alzheimer agents. Several processes have been suggested for the aptitude of flavonoids to slow down the advancement or to avert the onset of Alzheimer’s pathogenesis. To enhance cognitive performance and to prevent the onset and progress of AD, the interaction of flavonoids with various signaling pathways is proposed to exert their therapeutic potential. Therefore, this review elaborates on the probable therapeutic approaches of flavonoids aimed at averting or slowing the progression of the AD pathogenesis.

Ethnopharmacological Inspections of Organic Extract of Oroxylum indicum in Rat Models: A Promising Natural Gift

The stem bark of Oroxylum indicum (O. indicum) was aimed at testing for anti-inflammatory, antiulcerative, antihyperglycemic, and antidyslipidemic activities. Liver enzyme concentration (SGPT, SGOT) had also been assessed. After being extracted in organic solvent, 3 distinct doses, 100, 200, and 400 mg/kg b.w. (p.o.), were used. For edema formation 0.1 ml carrageenan at a dose of 1% w/v was injected into paw of left hind. It showed a fall of edemas 37.50%, 48.34%, and 55.83% while used doses were 100, 200, and 400 mg/kg b.w. (p.o.) individually. The EtOH extract of O. indicum (50%) and its fractions PET, CLF, EtOAc, and nBUT were studied against ethanol-induced gastric mucosal damage. Only PET and n-BuOH exhibited the highest percentage of protection and were 96% and 99%, respectively, persuaded by ethanol. In OGTT glibenclamide revealed reduction of glucose level to 7.55 ± 0.22 mmol/L from 10.57 ± 0.32 mmol/L after 30 minutes. Antihyperglycemic activities were assessed for 8- and 12-week duration in diabetic rats. Glibenclamide reduced glucose level from 33.50±0.31 to 7.90±0.19 mmol/L in 12 weeks. In 12 and 8 weeks, combination therapy lowered blood glucose level to a normal extent by 79% and 61% individually. In antidyslipidemic activities after 12-week treatment, it revealed simvastatin; MEOI (400 mg/kg b.w.) and combination of both reduced TC level by 44%, 28%, and 48% consequently followed by TG and LDL. In 8-week treatment, HDL levels were increased by 34%, 13%, and 36%, and in 12 weeks increased by 36%, 8%, and 38% consequently. Liver enzyme concentration after 12 weeks of treatment with glibenclamide, 400 mg/kg b.w. (p.o.) of MEOI and combination of both, exhibited the fact that concentration of SGPT showed downturn by 43.23%, 8.01%, and 54.86% and SGOT by 42.40%, 5.31%, and 44.85%. This study remarked that O. indicum has anti-inflammatory, antiulcer, antidiabetic, and antidyslipidemic potentials but has no ameliorative effect on liver enzyme.

Molecular mechanisms underlying protective role of quercetin in attenuating Alzheimer's disease

Quercetin belongs to the flavonoids family, which is present in most of the plants including fruits, vegetables, green tea and even in red wine having antioxidant activities. It is available as a food supplement in the market and has physiological health effects. Quercetin has anti-inflammatory, anticancer and anti-prostate activities along with its beneficial effects on high cholesterol, kidney transplantation, asthma, diabetes, viral infections, pulmonary, schizophrenia and cardiovascular diseases. Quercetin possesses scavenging potential of hydroxyl radical (OH^-), hydrogen peroxide (H₂O₂), and superoxide anion (O₂^-). These reactive oxygen species (ROS) hampers lipid, protein, amino acids and deoxyribonucleic acid (DNA) processing leading to epigenetic alterations. Quercetin has the ability to combat these harmful effects. ROS plays a vital role in the progression of Alzheimer's disease (AD), and we propose that quercetin would be the best choice to overcome cellular and molecular signals in regulating normal physiological functions. However, data are not well documented regarding exact cellular mechanisms of quercetin. The neuroprotective effects of quercetin are mainly due to potential up- and/or down-regulation of cytokines via nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Paraoxonase-2, c-Jun N-terminal kinase (JNK), Protein kinase C, Mitogen-activated protein kinase (MAPK) signalling cascades, and PI3K/Akt pathways. Therefore, the aim of the present review was to elaborate on the cellular and molecular mechanisms of the quercetin involved in the protection against AD.