Phytochemicals: Potential in Management of Climacteric Neurobiology.

Menopause jeopardizes the integrity of brain and makes it vulnerable to various diseases, both of psychiatric and degenerative nature. Exogenous estrogen supplementation confers neuroprotection but the results of Women's Health Initiative (WHI), Million Women Study (MWS) and incidence of endometrial cancer, breast cancer and venous thromboembolism reported with estrogen use have engendered doubts over its clinical translation for postmenopausal neurological disorders. Scientific community and general public have started recognizing the protective potential of phytochemicals in climacteric medicine. These phytochemicals are plant-derived, non-steroidal bioactive estrogenic compounds. Emerging preclinical studies have suggested that these phytochemicals display potential benefits in mitigating postmenopausal depression, anxiety, cerebral ischemia and cognitive dysfunction. Thus, the aim of present review is: a) to give an overview of neuroprotective action of estrogen, b) to address the chemical and pharmacological features of various classes of phytoestrogens, and c) to present preclinical and clinical evidence of effect of phytoestrogens on climacteric neurobiology with their possible mechanisms of action.

Lycopene abrogates Aß(1-42)-mediated neuroinflammatory cascade in an experimental model of Alzheimer's disease.

BACKGROUND: Neuroinflammation characterized by glial activation and release of proinflammatory mediators is considered to play a critical role in the pathogenesis of Alzheimer's disease (AD). ß-Amyloid1-42 (Aß1-42)-induced learning and memory impairment in rats is believed to be associated with neuronal inflammation. OBJECTIVES: The present study was designed to investigate the effect of lycopene, a potent antioxidant and anti-inflammatory carotenoid, in intracerebroventricular (i.c.v.) Aß1-42-induced neuroinflammatory cascade along with learning and memory impairment in rats. MATERIAL AND METHODS: I.c.v. Aß1-42 was injected bilaterally followed by treatment with lycopene or rivastigmine for 14 days. Morris water maze and elevated plus maze tests were used to assess the memory function. Rats were sacrificed and brains harvested to evaluate various biochemical parameters and mitochondrial complex activities in postmitochondrial supernatant fractions of cerebral cortex and hippocampus of rat brains. The levels of tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), tumor growth factor ß (TGF-ß), nuclear factor-κB (NF-κB) and caspase-3 were assessed by enzyme-linked immunosorbent assay analysis. RESULTS: Lycopene remediated Aß-induced learning and memory deficits in a dose-dependent manner. Aß1-42-induced mitochondrial dysfunction along with surge of proinflammatory cytokines TNF-α, TGF-ß and IL-1ß as well as NF-κB and caspase-3 activity in rat brain was significantly reduced with lycopene treatment. CONCLUSION: The amelioration of Aß1-42-induced spatial learning and memory impairment by lycopene could be linked, at least in part, to the inhibition of NF-κB activity and the down-regulation of expression of neuroinflammatory cytokines, suggesting that lycopene may be a potential candidate for AD treatment.

Neuroprotective potential of sesamol and its loaded solid lipid nanoparticles in ICV-STZ-induced cognitive deficits: behavioral and biochemical evidence.

Neuroinflammation is a prominent feature of Alzheimer disease (AD) and other chronic neurodegenerative disorders. Intracerebroventricular (ICV) streptozotocin (STZ) induced-cognitive impairment has been widely used as an experimental paradigm of Alzheimer׳s disease. Sesamol is a potent inhibitor of cytokine production as well as an antioxidant. The present study was designed to evaluate the effectiveness of sesamol in ICV-STZ-induced cognitive deficits in rats by incorporating it into solid lipid nanoparticles (SLNs). ICV-STZ administration produced significant cognitive deficits as assessed by both Morris water maze and elevated plus maze task which is accompanied by significantly enhanced nitrodative stress, altered acetylcholinesterase in rat brain along with significantly increased serum TNF-α levels. Chronic treatment with sesamol and sesamol loaded SLNs dose dependently restored cognitive deficits in ICV-STZ rats along with mitigation of nitrodative stress and cytokine release. Effectiveness of SLNs to deliver sesamol to the brain was shown by a significantly better alleviation of the oxidative stress parameters. Our findings demonstrate that loading of sesamol in SLNs is an effective strategy to mitigate ICV-STZ-induced neuronal dysfunction and memory deficits.

Epigallocatechin gallate ameliorates behavioral and biochemical deficits in rat model of load-induced chronic fatigue syndrome.

Chronic fatigue syndrome is a heterogeneous disorder with unknown pathogenesis and etiology, characterized by tiredness, difficulty in concentration and memory, and concomitant skeletal and muscular pain, thus affecting both mental and physical domains. The pathogenesis of chronic fatigue syndrome is multifactorial and involves increased oxido-nitrosative stress along with generation of pro-inflammatory cytokines such as TNF-α. In the present study chronic fatigue was produced in rats by plunging a load of 10 ± 2% body weight and subjecting them to forced swim inside a rectangular jar daily for 28 days. Endurance capacity and post-swim fatigue were assessed on 1st, 7th, 14th, 21st and 28th days. EGCG was administered daily by oral gavage 30 min before forced swim session. On the 29th day, after assessment of various behavioral parameters, blood was collected through tail vein, and animals were sacrificed to harvest the brains, spleens and thymus. Chronic fatigue group exhibited significant behavioral alterations along with enhanced oxido-nitrosative stress and serum TNF-α level as compared to naive group. Chronic treatment with EGCG restored all the behavioral and biochemical alterations associated with chronic fatigue syndrome. The present study signifies the therapeutic potential of EGCG for the treatment of chronic fatigue syndrome.

Protective effect of epigallocatechin gallate in murine water-immersion stress model of chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) is a specific clinical condition that characterizes unexplained disabling fatigue. In the present study, chronic fatigue was produced in mice by subjecting them to forced swim inside a rectangular jar of specific dimensions for 6 min. daily for 15 days. Epigallocatechin gallate (EGCG; 25, 50 and 100 mg/kg, p.o.) was administered daily 30 min. before forced swim session. Immobility period and post-swim fatigue was assessed on alternate days. On the 16th day, after assessment of various behavioural parameters, mice were killed to harvest the brain, spleen and thymus. There was significant increase in oxidative-nitrosative stress and tumour necrosis factor-alpha levels in the brain of mice subjected to water-immersion stress as compared with naive group. These behavioural and biochemical alterations were restored after chronic treatment with EGCG. The present study points out that EGCG could be of therapeutic potential in the treatment of chronic fatigue.

Epigallocatechin gallate ameliorates chronic fatigue syndrome in mice: behavioral and biochemical evidence.

Three decades after the coining of the term chronic fatigue syndrome, the diagnosis of this illness is still symptom based and the aetiology remains elusive. Chronic fatigue syndrome pathogenesis seems to be multifactorial and the possible involvement of immune system is supported. The present study was designed to evaluate the effects of the epigallocatechin gallate in a mouse model of immunologically induced chronic fatigue. On 19th day, after lipopolysaccharide/Brucella abortus administration, the mice showed significant increase in immobility period, post swim fatigue and thermal hyperalgesia. Behavioral deficits were coupled with enhanced oxidative-nitrosative stress as evident by increased lipid peroxidation, nitrite levels and decreased endogenous antioxidant enzymes (superoxide dismutase, reduced glutathione and catalase) and inflammation (increased levels of tumor necrosis factor-alpha and tissue growth factor-beta). Chronic treatment with epigallocatechin gallate restored these behavioral and biochemical alterations in mice. The present study points out towards the beneficial effect of epigallocatechin gallate in the amelioration of chronic fatigue syndrome and thus may provide a new, effective and powerful strategy to treat chronic fatigue syndrome.

Attenuation of renoinflammatory cascade in experimental model of diabetic nephropathy by sesamol.

Diabetes has become the most common single cause of end-stage renal disease (ESRD) in the United States and Europe. Approximately 30-40% of patients with type I and 15% with type II diabetes mellitus develop end ESRD. The study was designed to evaluate the impact of sesamol on renal function and renoinflammatory cascade in streptozotocin (STZ)-induced diabetes. STZ-induced diabetic rats were treated with sesamol (2, 4, and 8 mg/kg/day; po) or with vehicle from the fifth to eighth weeks. After 8 weeks, urine albumin excretion, urine output, serum creatinine, blood urea nitrogen, creatinine, and urea clearance were measured. Cytoplasmic and nuclear fractions of kidney were prepared for the quantification of oxidative-nitrosative stress (lipid peroxidation, superoxide dismutase, catalase, nonprotein thiols, total nitric oxide), tumor necrosis factor-alpha (TNF-alpha), tissue growth factor-1 beta (TGF-beta1), p65 subunit of NFkappabeta, and caspase-3. After 8 weeks of STZ injection, the rats produced significant alteration in renal function, increased oxidative-nitrosative stress, TNF-alpha, TGF-beta1, caspase-3 activity in cytoplasmic lysate, and active p65 subunit of NFkappabeta in nuclear lysate of kidney of diabetic rats. Interestingly, co-administration of sesamol significantly and dose-dependently prevented biochemical and molecular changes associated with diabetes. Moreover, diabetic rats treated with insulin-sesamol combination produced more pronounced effect on molecular parameters as compared to their respective groups. The data reveal that sesamol modulates the release of profibrotic cytokines, oxidative stress, ongoing chronic inflammation, and apoptosis and thus exerts a marked renoprotective effect.