Protective effects of pre-germinated brown rice diet on low levels of Pb-induced learning and memory deficits in developing rat

Natural Products-based Drugs: Potential Drug Targets Against Neurological Degeneration

Phytochemicals or natural products have been studied extensively for their potential in the treatment of neurodegenerative diseases (NDs) like Parkinson's disease, Alzheimer's disease, etc. The neuronal structure loss and progressive dysfunction are the main characteristics of these diseases. In spite of impressive and thorough knowledge of neurodegenerative molecular pathways, little advancement has been found in the treatment of the same. Moreover, it was proved that natural products can be used efficiently in the treatment of NDs while certain issues regarding the patient's safety and clinical data are still existing. As ND is a bunch of diseases and it will start the myriad of pathological processes, active targeting of the molecular pathway behind ND will be the most efficient strategy to treat all ND-related diseases. The targeting pathway must prevent cell death and should restore the damaged neurons. In the treatment of ND and related diseases, natural products are playing the role of neuroprotective agents. This review will target the therapeutic potential of various phytochemicals which shows neuroprotective action.

Modulation of High-Fat Diet-Induced Brain Oxidative Stress by Ferulate-Rich Germinated Brown Rice Ethyl Acetate Extract

The oxidative stress resulting from the production of reactive oxygen species plays a vital role in inflammatory processes and is associated with neurodegenerative changes. In view of the ability of germinated brown rice (GBR) to improve learning and memory, this present study aimed to investigate the mechanistic basis of GBR’s neuroprotection in a high-fat diet (HFD)-induced oxidative changes in adult Sprague–Dawley rats. Ferulate-rich GBR ethyl acetate extract (GBR-EA; 100 mg/kg and 200 mg/kg body weight) was supplemented orally for the last 3 months of 6 months HFD feeding during the study. GBR-EA supplementation was found to improve lipid profile and serum antioxidant status, when compared to the HFD group. Elevated mRNA expressions of SOD1, SOD2, SOD3, Catalase, and GPX were demonstrated in the frontal cortex and hippocampus of GBR-EA treated animals. The pro-inflammatory changes induced by HFD in the hippocampus were attenuated by GBR-EA through the downregulation of CRP and TNF- α and upregulation of PPAR-γ. GBR also reduced the hippocampal mRNA expression and enzyme level of acetylcholinesterase. In conclusion, this study proposed the possible transcriptomic regulation of antioxidant and inflammation in neurodegenerative processes resulting from high cholesterol consumption, with an emphasis on GBR’s potential to ameliorate such changes.

Germinated Brown Rice Attenuates Cell Death in Vascular Cognitive Impaired Mice and Glutamate-Induced Toxicity In HT22 Cells

Germinated brown rice (GBR) with unpolishing, soaking, and germinating processes can improve the texture, flavor, and nutritional value, including GABA and phenolic contents. The effect of GBR was first investigated in vascular cognitive impaired mice and glutamate-induced toxicity in HT22 cells with respect to standard pure GABA. Feeding mice with GBR for 5 weeks showed neuroprotection. In this study, the modified bilateral common carotid artery occlusion mice model was mild but a significant difference in cognitive impairment was still shown. Like pure GABA, GBR decreased cognitive deficits in memory behavioral tests and significantly attenuated hippocampal neuronal cell death at P < 0.001. Similarly to 0.125 μM of GABA, 100 μg/mL of GBR increased HT22 cell viability after glutamate toxicity. GBR affected less apoptotic cell death and less blocking by the GABA_A antangonist bicuculline in comparison to GABA. When the results are taken together, the underlying mechanism of GBR protection may mediate though the GABA_A receptor and its phenolic contents.

Anticonvulsant and Neuroprotective Activities of Phragmanthera austroarabica Extract in Pentylenetetrazole-Kindled Mice

Anticonvulsant and neuroprotective activity of Phragmanthera austroarabica extract were tested in pentylenetetrazole-kindled mice. All the chemical constituents of the plant extract were identified. Additionally, the extract was standardized and proved to contain total phenolic contents equal to 379.92 ± 1.32 mg gallic acid equivalents/g dry plant extract. Induction of kindling was achieved by repeated intraperitoneal administration of pentylenetetrazole (35 mg/kg) twice weekly. Male albino mice were given P. austroarabica extract (200, 400, or 800 mg/kg). The two higher doses (400 or 800 mg/kg) of the extract significantly caused notable reduction in seizure activity and hippocampal malondialdehyde level compared to pentylenetetrazole control group. The highest dose enhanced cortical GSH level and showed intact DNA in the laddering assay. Upon studying the neuroprotective effect, mice treated with the higher dose of the extract demonstrated an improvement in the percent of surviving neurons in the cortex and hippocampus. We concluded that P. austroarabica extract ameliorated seizure activity and protected cortical and hippocampal neurons against pentylenetetrazole-induced kindling in mice.

Recovery effect of pre-germinated brown rice on the alteration of sperm quality, testicular structure and androgen receptor expression in rat model of depression

Depression and antidepressant drugs induce adverse effects in male reproduction. Therefore, it is important to investigate alternative treatment for depression without adverse effects on the male reproductive system. The aim of this study was to determine the effect of pre-germinated brown rice (PGBR) on sperm quality, testicular structure and androgen receptor (AR) expression in rat model of depression. Male Sprague Dawley rats were divided into five groups including control (distilled water only), depression induced by forced swimming test (FST), FST + fluoxetine (antidepressant drug), FST + GABA (gamma-aminobutyric acid) (standard) and FST + PGBR. When compared with the control, sperm motility showed a significant decrease in FST + fluoxetine group. Sperm morphology also decreased significantly in depression and FST + fluoxetine groups. The morphological changes of seminiferous tubules showed significant increases in depression and FST + fluoxetine groups, while AR expression showed significant decreases in depression, FST + fluoxetine and FST + GABA groups. Interestingly, there were no significant differences in all sperm quality parameters, testicular structure and AR expression in FST + PGBR group. These findings reflect the recovery effects of PGBR treatment on sperm quality, morphological changes of seminiferous tubules and AR expression in stress-induced rats. Therefore, PGBR may potentially develop for the treatment for depression without adverse effect on male reproduction.

The protective effect of grape seed procyanidin extract against cadmium-induced renal oxidative damage in mice

As an important environmental pollutant, cadmium (Cd) can lead to serious renal damage. Grape seed procyanidins extract (GSPE), a biological active component of grape seed, has been shown to possess antioxidative effects. Here, we assessed the protective effect of GSPE on Cd-induced renal damage using animal experiment. After 30 days, the oxidative damage of kidney was evaluated through measurement of superoxide dismutase (SOD), glutathione peroxidation (GSH-Px) and malondialdehyde (MDA). Since, oxidative stress could lead to apoptosis, the renal apoptosis was measured using flow cytometer. Moreover, the expression of apoptosis-related protein Bax and Bcl-2 was analyzed by immunohistochemistry and Western blot. The results showed that Cd led to the decrease of SOD and GSH-Px activities, and the increase of MDA level, induced renal apoptosis. However, the coadministration of GSPE attenuated Cd-induced lipid peroxidation, and antagonized renal apoptosis, probably associated with the expression of Bax and Bcl-2. These data suggested that GSPE has protective effect against renal oxidative damage induced by Cd, which provide a potential natural chemopreventive agent against Cd-poisoning.

Upregulation of genes related to bone formation by γ-amino butyric acid and γ-oryzanol in germinated brown rice is via the activation of GABAB-receptors and reduction of serum IL-6 in rats

Background

Osteoporosis and other bone degenerative diseases are among the most challenging non-communicable diseases to treat. Previous works relate bone loss due to osteoporosis with oxidative stress generated by free radicals and inflammatory cytokines. Alternative therapy to hormone replacement has been an area of interest to researchers for almost three decades due to hormone therapy-associated side effects.

Methods

In this study, we investigated the effects of gamma-amino butyric acid (GABA), gamma-oryzanol (ORZ), acylated steryl glucosides (ASG), and phenolic extracts from germinated brown rice (GBR) on the expression of genes related to bone metabolism, such as bone morphogenic protein-2 (BMP-2), secreted protein acidic and rich in cysteine (SPARC), runt-related transcription factor 2 (RUNX-2), osteoblast-specific transcription factor osterix (Osx), periostin, osteoblast specific factor (Postn), collagen 1&2 (Col1&2), calcitonin receptor gene (CGRP); body weight measurement and also serum interleukin-6 (IL-6) and osteocalcin, in serum and bone. Rats were treated with GBR, ORZ, GABA, and ASG at (100 and 200 mg/kg); estrogen (0.2 mg/kg), or remifemin (10 and 20 mg/kg), compared to ovariectomized non-treated group as well as non-ovariectomized non-treated (sham) group. Enzyme-linked immunosorbent assay was used to measure the IL-6 and osteocalcin levels at week 2, 4, and 8, while the gene expression in the bone tissue was determined using the Genetic Analysis System (Beckman Coulter Inc., Brea, CA, USA).

Results

The results indicate that groups treated with GABA (100 and 200 mg/kg) showed significant upregulation of SPARC, calcitonin receptor, and BMP-2 genes (P < 0.05), while the ORZ-treated group (100 and 200 mg/kg) revealed significant (P < 0.05) upregulation of Osx, Postn, RUNX-2, and Col1&2. Similarly, IL-6 concentration decreased, while osteocalcin levels increased significantly (P < 0.05) in the treated groups as compared to ovariectomized non-treated groups.

Conclusion

GABA and ORZ from GBR stimulates osteoblastogenesis by upregulation of bone formation genes, possibly via the activation of GABA_B receptors and by inhibiting the activity of inflammatory cytokines and reactive oxygen species. Therefore, it could be used effectively in the management of osteoporosis.

Germinated brown rice and its bioactives modulate the activity of uterine cells in oophorectomised rats as evidenced by gross cytohistological and immunohistochemical changes

Background

Germinated brown rice (GBR) is gaining momentum in the area of biomedical research due to its increased use as a nutraceutical for the management of diseases. The effect of GBR on the reproductive organs of oophorectomised rats was studied using the gross, cytological, histological and immunohistochemical changes, with the aim of reducing atrophy and dryness of the genital organs in menopause.

Methods

Experimental rats were divided into eight groups of six rats per group. Groups 1, 2 and 3 (sham-operated (SH), oophorectomised without treatment (OVX) and oophorectomised treated with 0.2 mg/kg oestrogen, respectively) served as the controls. The groups 4,5,6,7 and 8 were treated with 20 mg/kg Remifemin, 200 mg/kg of GBR, ASG, oryzanol and GABA, respectively. All treatments were administered orally, once daily for 8 weeks. Vaginal smear cytology was done at the 7^th week on all the rats. The weight and dimensions of the uterus and vagina were determined after sacrifice of the rats. Uterine and vaginal tissues were taken for histology and Immunohistochemical examinations.

Results

GBR and its bioactives treated groups significantly increased the weight and length of both the uterus and the vagina when compared to Oophorectomised non-treated group (OVX-non-treated) (p < 0.05). Significant changes were observed in the ratio of cornified epithelial cells and number of leucocytes in the vaginal cytology between the oophorectomised non-treated and treated groups. There was also an increase in the luminal and glandular epithelial cells activity in the treated compared with the untreated groups histologically. Immunohistochemical staining showed specific proliferating cell nuclear antigen (PCNA) in the luminal and glandular epithelium of the treated groups, which was absent in the OVX-non-treated group. GBR improved the length and weight of the uterus and also increased the number of glandular and luminal cells epithelia of the vagina.

Conclusion

GBR and its bioactives could be a potential alternative in improving reproductive system atrophy, dryness and discomfort during menopause.

Effect of food azo dye tartrazine on learning and memory functions in mice and rats, and the possible mechanisms involved

Tartrazine is an artificial azo dye commonly used in human food and pharmaceutical products. The present study was conducted to evaluate the toxic effect of tartrazine on the learning and memory functions in mice and rats. Animals were administered different doses of tartrazine for a period of 30 d and were evaluated by open-field test, step-through test, and Morris water maze test, respectively. Furthermore, the biomarkers of the oxidative stress and pathohistology were also measured to explore the possible mechanisms involved. The results indicated that tartrazine extract significantly enhanced active behavioral response to the open field, increased the escape latency in Morris water maze test and decreased the retention latency in step-through tests. The decline in the activities of catalase, glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) as well as a rise in the level of malonaldehyde (MDA) were observed in the brain of tartrazine-treated rats, and these changes were associated with the brain from oxidative damage. The dose levels of tartrazine in the present study produced a few adverse effects in learning and memory functions in animals. The mechanisms might be attributed to promoting lipid peroxidation products and reactive oxygen species, inhibiting endogenous antioxidant defense enzymes and the brain tissue damage.

PRACTICAL APPLICATION

Tartrazine is an artificial azo dye commonly used in human food and pharmaceutical products. Since the last assessment carried out by the Joint FAO/WHO Expert Committee on Food Additives in 1964, many new studies have been conducted. However, there is a little information about the effects on learning and memory performance. The present study was conducted to evaluate the toxic effect of tartrazine on the learning and memory functions in animals and its possible mechanism involved. Based on our results, we believe that more extensive assessment of food additives in current use is warranted.

Neuroprotective effects of germinated brown rice against hydrogen peroxide induced cell death in human SH-SY5Y cells

The neuroprotective and antioxidative effects of germinated brown rice (GBR), brown rice (BR) and commercially available γ-aminobutyric acid (GABA) against cell death induced by hydrogen peroxide (H(2)O(2)) in human neuroblastoma SH-SY5Y cells have been investigated. Results show that GBR suppressed H(2)O(2)-mediated cytotoxicity and induced G0/G1 phase cell cycle arrest in SH-SY5Y cells. Moreover, GBR reduced mitochondrial membrane potential (MMP) and prevented phosphatidylserine (PS) translocation in SH-SY5Y cells, key features of apoptosis, and subsequent cell death. GBR exhibited better neuroprotective and antioxidative activities as compared to BR and GABA. These results indicate that GBR possesses high antioxidative activities and suppressed cell death in SH-SY5Y cells by blocking the cell cycle re-entry and apoptotic mechanisms. Therefore, GBR could be developed as a value added functional food to prevent neurodegenerative diseases caused by oxidative stress and apoptosis.