Search

Tobacco smoke is not only a leading cause for chronic obstructive pulmonary disease, cardiovascular disorders, and lung and oral cancers, but also causes neurological disorders such as Alzheimer ’s disease. Tobacco smoke consists of more than 4500 toxic chemicals, which form free radicals and can cross blood-brain barrier resulting in oxidative stress, an extracellular amyloid plaque from the aggregation of amyloid β (Aβ) peptide deposition in the brain. Further, respiratory infections such as Chlamydia pneumoniae, respiratory syncytial virus have also been involved in the induction and development of the disease. The necessary information collated on this review has been gathered from various literature published from 1995 to 2019. The review article sheds light on the role of smoking and respiratory infections in causing oxidative stress and neuroinflammation, resulting in Alzheimer's disease (AD). This review will be of interest to scientists and researchers from biological and medical science disciplines, including microbiology, pharmaceutical sciences and the translational researchers, etc. The increasing understanding of the relationship between chronic lung disease and neurological disease is two-fold. First, this would help to identify the risk factors and possible therapeutic interventions to reduce the development and progression of both diseases. Second, this would help to reduce the probable risk of development of AD in the population prone to chronic lung diseases.

The current study elucidates pharmacological evaluation of bromelain as a bioactive compound obtain from pineapple stem belongs to family Bromeliaceae in AlCl3 and D - galactose induced mice. In mice, co-administration of AlCl3 at dose 5 mg/kg b.w., via the oral route, and D - galactose at dose 60 mg/kg b.w., via intraperitoneal route for 90 days resulted in cognitive impairment, spatial learning, and memory deficits, as well as neurotoxicity. However, 30 consecutive days, treatments via an intraperitoneal route with bromelain low dose (Brm L) at dose 10 mg/kg b.w., bromelain high dose (Brm H) at dose 20 mg/kg b.w., donepezil (Dnpz) at dose 2 mg/kg b.w., and Brm L + Dnpz at doses 10, 2 mg/kg b.w. were considerably reversed the effect of AlCl3 and D - galactose induced AD mice. Consequences of behavioral parameters (Morris water maze, elevated plus maze and locomotor), biochemical estimation (MDA, GSH, SOD, CAT, Nitrite and AChE), and ELISA tests (mouse BACE, Aβ1 - 42, TNF-α, IL-6, and BDNF) confirmed significant (p

Abstract: The human gut microbiota plays a significant role in the pathophysiology of central nervous system-related diseases. Recent studies suggest correlations between the altered gut microbiota and major depressive disorder (MDD). It is proposed that normalization of the gut microbiota alleviates MDD. The imbalance of brain-gut-microbiota axis also results in dysregulation of the hypothalamicpituitary- adrenal (HPA) axis. This imbalance has a crucial role in the pathogenesis of depression. Treatment strategies with certain antibiotics lead to the depletion of useful microbes and thereby induce depression like effects in subjects. Microbiota is also involved in the synthesis of various neurotransmitters (NTs) like 5-hydroxy tryptamine (5-HT; serotonin), norepinephrine (NE) and dopamine (DA). In addition to NTs, the gut microbiota also has an influence on brain derived neurotrophic factor (BDNF) levels. Recent research findings have exhibited that transfer of stress prone microbiota in mice is also responsible for depression and anxiety-like behaviour in animals. The use of probiotics, prebiotics, synbiotics and proper diet have shown beneficial effects in the regulation of depression pathogenesis. Moreover, transplantation of fecal microbiota from depressed individuals to normal subjects also induces depression-like symptoms. With the precedence of limited therapeutic benefits from monoamine targeting drugs, the regulation of brain-gut microbiota is emerging as a new treatment modality for MDDs. In this review, we elaborate on the significance of brain-gut-microbiota axis in the progression of MDD, particularly focusing on the modulation of the gut microbiota as a mode of treating MDD.