Objective: The present study was designed to evaluate the neuroprotective effect of methanolic extract of Sargassum wightii on haloperidolinduced catalepsy and tardive dyskinesia in Wistar albino rats. Methods:In this study, thirty Wistar albino rats were randomly divided into six groups. Gr-I served as control. Haloperidol (1 mg/kg intraperitoneally) was administered to rats of Gr-II to Gr-V for twenty-one consecutive days to induce catalepsy and tardive dyskinesia. Animals of Gr-II to Gr-V were orally administered with vehicle, levodopa carbidopa combination (30 mg/kg), Sargassum extract 200 and 400 mg/kg respectively. All the drugs and vehicles were given orally one hour before haloperidol injection for twenty one consecutive days. The cataleptic scores were recorded using standard bar test. Tardive dyskinesia was assessed in terms of vacuous chewing movement (VCM) and tongue protrusion (TP) scores. After behavioural testing, all animals were sacrificed on twenty-second day and various biochemical parameters like MDA, SOD and GSH were estimated in brain tissue.Results: Chronic administration of haloperidol significantly increased cataleptic scores, VCM and TP scores. (p<0.001) Sargassum wightii extract (400 mg/kg) significantly inhibited haloperidol-induced catalepsy, VCM and TP (p<0.001) Haloperidol increased MDA and decreased SOD and GSH in brain tissue to a highly significant extent (p<0.001) Sargassum extract at 400 mg/kg also significantly reversed the haloperidol-induced alteration in brain oxidative stress markers. Conclusion:Sargassum wightii inhibits haloperidol-induced catalepsy and tardive dyskinesia. Thus it may be used as a unique therapeutic adjunct for the prevention of neuroleptic-induced extrapyramidal symptoms, however, it has to be explored more.

Introduction: Antioxidants of natural sources for the treatment of many ailments have taken priority since the last decades. Recently, researches have been focused on marine algae as they are the largest reservoir of bioactive compounds. Hence, the objective of this study was to explore the in-vitro antioxidant and anti-inflammatory activities of methanolic and aqueous extracts of Sargassum wightii. Methods: The total phenolics, flavonoids, and ascorbic acid (AA) contents were evaluated informs of gallic acid equivalent (GAE), rutin equivalent (RUE), and AA equivalent, respectively. The aqueous and methanolic extracts were isolated. The antioxidant activities were explored using2,2-diphenyl-1-picrylhydrazil (DPPH), superoxide dismutase (SOD), hydroxyl radical scavenging, and ferric reducing power assays. The in vitro anti-inflammatory activity was assayed using nitric oxide radical scavenging, inhibition of protein denaturation, and antiproteinase activities. Results: We observed significant changes in DPPH scavenging activity with both methanolicSargassum extract (MSE) and aqueous Sargassum extract (ASE) [IC50: 511.15 µg/mL and 927.05µg/mL, respectively]. Methanolic extract showed a greater SOD scavenging activity [IC50: 369.56µg/mL] and hydroxyl radical scavenging potential [IC50: 668.93 µg/mL] than that of ASE [SOD,IC50: 923.94 µg/mL; hydroxyl ion, IC50: 953.57 µg/mL]. In the Ferric reducing antioxidant power assay, MSE and ASE exhibited absorbance of 0.93±0.12 and 0.59±0.08, respectively, at 1200 µg/mL each. Both methanol and ASEs showed NO– scavenging activity having IC50 in order, AA(96.46 µg/mL) <MSE (963.50 µg/mL) <ASE (1974.88 µg/mL). However, the protein denaturation inhibition and antiproteinase activity of both these extracts at 1000 µg/mL were similar. Conclusion: Sargassum wightii has promising antioxidant and anti-inflammatory activities and could be a potential candidate for drug development targeting oxidative stress-mediated inflammatory diseases.

Sargassum wightii is brown seaweeds with high nutritive value with natural bioactive compounds having diverse therapeutic activity. In recent years, research on Sargassum wightii has gain much interest in neuropharmacological field. Basing on neuroprotective effect of Sargassum wightii against Parkinson’s disease animal models, the possible protective effect on dementia is hypothesised. Addressing this question the present study was designed to investigate the effect of S. wightii on L-methionine induced vascular dementia like syndrome in male wistar albino rats. Vascular dementia was induced by oral administration of L-methionine (1.7 g/kg) per body weight for 4weeks S. wightii was given from day1 to day32. The neurobehavioral assessment was performed by Morris water maze test for learning and memory ability and blood sample was collected for serum nitrite and homocysteine analysis. The whole brain content was subjected to a series of biochemical analysis that included brain cholinesterase, malondialdehyde, reduced glutathione and histopathological examination. L-methionine impaired learning and memory, increased serum homocysteine and decreased serum nitrite level significantly (p<0.001). It also increased brain thiobarbituric acid reactive substances, reduced glutathione and increased acetylcholinesterase activity significantly (p<0.001). Sargassum wightii at 200mg/kg and 400mg/kg body weight reversed the L-methionine induced learning and memory deficits (p<0.01) and (p<0.001) respectively. The L-methionine induced biochemical alterations in serum and brain as well as histopathological aberration in cortex and hippocampus were restored by Sargassum wightii (p<0.01). This study concluded that Sargassum wightii ameliorated L-methionine induced vascular dementia like syndrome and provided a new concept in anti-dementia therapy as a neuroprotectants.

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Introduction: The pathogenesis of Parkinson’s disease (PD) is multifactorial in which oxidative stress, neuroinflammation, and mitochondrial dysfunction are the leading factors. Currently, the antioxidant and anti-inflammatory agents of natural sources as neuroprotectants have raised much attention. The current study aimed to explore the neuroprotective effect of methanolic extract of Sargassum wightii in male Wistar albino rats against rotenone-induced PD. Methods: The rats were administered with rotenone (10 mg/kg orally) daily for 28 days to induce PD. S. wightii (200 mg/kg and 400 mg/kg) and levodopa+carbidopa combination (10 mg/kg) were administered to different groups of rats one hour prior to rotenone for 28 days. Behavioral parameters (akinesia, tremor, motor coordination, and locomotor activities) and body weight were recorded on days 14th and 28th of drug treatment. On the 28th day, the animals were sacrificed for the neurobiochemical analyses of brain tissue. Results: Rotenone treatment caused a significant reduction in behavioural parameters (P < 0.001), neurochemical deficits (P < 0.001), and elevation of oxidative stress markers (P < 0.001) in the brain. Pre-treatment with S. wightii at 200 mg/kg and 400 mg/kg doses significantly attenuated the rotenone-induced behavioral alterations and restored the mitochondrial NADH dehydrogenase activity and dopamine level in the striatum (P < 0.001). Moreover, 400 mg/kg of S. wightii restored the rotenone-induced increased oxidative stress markers like malondialdehyde (MDA), superoxide dismutase (SOD), and reduced glutathione (GSH) in the striatum (P < 0.01). Conclusion: S. wightii has provided a neuroprotective effect, probably by virtue of its antioxidant and dopamine restoring potential. Hence, it may offer a promising and new therapeutic lead for the treatment of PD but needs further research.