Betaine attenuates oxidative stress and cognitive dysfunction in an amyloid ß-induced rat model of Alzheimer's disease.

Background and purpose: Increasing evidence indicates that oxidative stress is an important factor in the pathogenesis and progression of Alzheimer's disease (AD). Betaine is trimethylglycine with antioxidant and neuroprotective properties. The present study aimed to evaluate the possible beneficial effects of betaine on oxidative stress and memory deficits induced by intrahippocampal injection of amyloid beta (Aß) in an AD model. Experimental approach: Forty adult male Wistar rats were divided into 5 equal groups: the control and Aß groups which received oral gavage of saline (1 mL daily) for 14 days. The other 3 groups (betaine + Aß) received betaine (5, 10, and 15 mg/kg, orally) for 14 consecutive days. On the 15th day, all of the groups were injected bilaterallyintrahippocampal of Aß (5 µg/µL), except controls that were injected with normal saline as a vehicle. Seven days after the Aß injection, memory was assessed in a passive avoidance test. Changes in catalase activities and glutathione peroxidase, glutathione, and malondialdehyde concentrations were investigated to determine the antioxidant activity in the rat hippocampus. Findings/Results: Data showed that betaine pretreatment of Aß-injected rats improved memory in avoidance tasks. In addition, betaine pretreatment attenuated oxidative stress. Conclusion and implications: The current findings showed that oral administration of betaine could prevent Aß-induced impairment of memory possibly through suppression of oxidative stress in the hippocampus area of rats.

Effect of the Non-N-Methyl-D-aspartate Receptor of the Glutamatergic System of the Pedunculopontine Tegmental Nucleus on Cardiovascular Responses in Normotensive and Hydralazine-Induced Hypotensive Rats.

Background: Glutamate is an important excitatory neurotransmitter in the pedunculopontine tegmental (PPT) nucleus. The cardiovascular effect of glutamate and its non-N-methyl-D-aspartate (NMDA) receptor in the PPT is unknown; therefore, we evaluated glutamate and its non-NMDA receptor on cardiovascular parameters in normotensive and hypotensive induced by hydralazine (HLZ) in rat. Materials and Methods: After anesthesia, the femoral artery was cannulated for recording of cardiovascular parameters. Microinjection of drugs was done stereotaxically. L-Glutamate (L-Glu) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) (an antagonist of nonNMDA receptor) were microinjected into the PPT in normotensive and HLZ hypotensive rats. Changes (Δ) of mean arterial pressure (MAP), systolic blood pressure (SBP), and heart rate (HR) were obtained and compared with the control group. Results: In normotensive rats, L-Glu significantly increased SBP and MAP (P < 0.001) and decreased HR (P < 0.01), whereas CNQX alone did not significantly effect. Coinjection L-Glu + CNQX significantly attenuates the cardiovascular effect of L-Glu (P < 0.05 to P < 0.01). In hypotension induced by HLZ, SBP and MAP significantly decrease but HR did not change. In HLZ groups, L-Glu significantly improves (P < 0.05) and CNQX deteriorated hypotension induced by HLZ (P < 0.05). Coinjection of L-Glu + CNQX also attenuates the effect of L-Glu on Δ MAP and Δ SBP. In hypotension, ΔHR induced by L-Glu was significantly higher than CNQX (P < 0.01). In L-Glu + CNQX group, ΔHR also was lower than L-Glu (P < 0.05). Conclusion: Our findings revealed that glutamatergic system of the PPT in both normotensive and hypotension induced by HLZ plays a pressor with bradycardic responses that partly mediated by non-NMDA receptor.

Effect of MK-801, an antagonist of NMDA receptor in the pedunculopontine tegmental nucleus, on cardiovascular parameters in normotensive and hydralazine hypotensive rats.

Objectives: In the present study, the cardiovascular effects of glutamate NMDA receptor of the pedunculopontine tegmental nucleus (PPT) in normotensive and hydralazine (HLZ) hypotensive rats were evaluated. Materials and Methods: In the normotensive condition, MK-801(1 nmol; an NMDA receptor antagonist) and L-glutamate (L-Glu, 50 nmol an agonist) alone and together were microinjected into the nucleus using a stereotaxic device. In hypotensive condition, 2 min after induction of hypotension by HLZ (10 mg/kg, intravenous), drugs, same as in normotensive condition, were microinjected into the PPT. Recorded mean arterial pressure (MAP), systolic blood pressure (SBP), and heart rate (HR) were recorded throughout the experiment by a Power lab apparatus that was connected to a catheter inserted into the femoral arty. The cardiovascular changes (Δ) induced by microinjection drugs were computed and statistically analyzed. Results: In the normotensive condition, L-Glu significantly increased ΔMAP and ΔSBP (P<0.001) and decreased ΔHR (P<0.01) compared with the control. MK-801 alone significantly increased HR (P<0.05) while co-injected with L-Glu + MK-801 it significantly attenuated the L-Glu effect on ΔMAP and ΔSBP but augmented ΔHR (P<0.01). In the hydralazine hypotension condition, L-Glu significantly improved hypotension (P<0.01) and deteriorated bradycardia induced by HLZ (P<0.05). MK-801 alone did not significantly affect ΔMAP, ΔSBP, and ΔHR but when co-injected with L-Glu (L-Glu + MK-801) it could significantly attenuate the cardiovascular effect of L-Glu in the PPT. Conclusion: We found that activation of NMDA receptors of the glutamatergic system in the PPT evoked blood pressure and inhibited HR in both normotensive and hypotensive conditions in rats.

Dietary uptake of Salvia macilenta extract improves Nrf2 antioxidant signaling pathway and diminishes inflammation and apoptosis in amyloid beta-induced rats.

BACKGROUND: Studies showed the protective role of Salvia in traditional medicine against neurodegenerative diseases. Salvia macilenta is one of the potent antioxidant herbs among Salvia species against oxidative stress. In the current study, the effect of oral administration of S. macilenta in the antioxidant, anti-inflammatory activities of Aß-injected male albino Wistar rats was determined. METHODS: Rats were received S. macilenta (50 mg/kg/day) orally, for ten successive days and then some of them received Aß (10 ng/µl) in their hippocampus (CA1 region). Proteins involved in antioxidant defense system and inflammatory signaling pathways in the hippocampus and prefrontal cortex were evaluated using Western blotting technique. To study apoptosis, Western blotting technique and histological staining were used. Catalase activity, glutathione peroxidase (GSH) and nitric oxide levels were measured. RESULTS: Results demonstrated that S. macilenta increased Nrf2 protein level and decreased TNFα and IL-6 protein level in Aß-injected rats compared to the Aß-injected group in the hippocampus and prefrontal cortex. Histological analysis showed pretreatment with S. macilenta decreased apoptosis levels in the hippocampus and prefrontal cortex, about 41 and 42%, compared to Aß-injected rats, respectively. This study showed that catalase activity was changed in the S. macilenta + Aß group compared to the Aß-injected rats. Also, GSH level was increased in the S. macilenta + Aß group compared to the Aß-injected rat. CONCLUSION: Orally treatment of S. macilenta extract in Aß-injected rats could ameliorate protective pathways and, so, it can be one of the proposed dietary supplements for the prevention of Alzheimer's disease and dementia.

Biosynthesis and characterisation of solid lipid nanoparticles and investigation of toxicity against breast cancer cell line.

Solid lipid nanoparticles (SLNs) comprise non-toxic surface-active lipidic agents combined with appropriate ratios of drugs or essential oils. The goal of this research was to investigate the effects of the SLN synthesised using essential oils of Foeniculum vulgare on the MCF-7 breast cancer cell line. SLNs were prepared by homogenisation and ultrasound techniques and characterised by dynamic light scattering (DLS), zeta potential assessment, and transmission electron microscopy (TEM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT assay), flow-cytometry, and Acridine-Orange assay were employed for assessing the biological activities of the SLNs. The average particle size was 55.43 nm and the net surface charge was -29.54 ± 11.67 mV. TEM showed that the mean particle size was 33.55 nm and the synthesised SLNs had a uniform round morphology. The MTT assay showed that the prepared SLNs had high toxicity against MCF-7 cells and low toxicity against normal HUVECs cells. Flow-cytometry revealed a noteworthy rise in the subG1 peak of the cell cycle in the cancer cells treated with SLNs compared to the controls, indicating apoptosis in cancer cells. The results also showed discolouration in SLNs-treated cells, which further confirmed the induction of apoptosis and the toxicity of the SLNs against MCF-7 cells.

Design of new truncated derivatives based on direct and reverse mirror repeats of first six residues of Caerin 4 antimicrobial peptide and evaluation of their activity and cytotoxicity.

Caerin 4 is a family of AMPs isolated from the frog called Litoria caerulea. In silico drug designing methods and using machine learning algorithms for AMPs design can reduce their usage restrictions such as production costs and the time required for investigation of their activity and toxicity. In this study, two short peptides were designed based on direct and reverse mirror repeats of GLWQKI conserved sequence from Caerin 4 family that called dCar12 and rCar12. Also, Caerin 4.1 was synthesized without primary GLWQKI sequence and named Car7-23 . Following the synthesis of peptides, their antimicrobial properties, cytotoxicity, secondary structure, and mode of action were further evaluated. Results indicated that rCar12 had a good antibacterial activity (at an MIC of 3.9-62.5 µg/ml), while Car7-23 did not have any antimicrobial properties. Cytotoxicity of rCar12 at MICs range was <5%, which is much less than Caerin 4.1. In conclusion, rCar12 with reverse mirror repeat has different functional properties compared with dCar12. These results corroborate the fact that in two peptides with identical residues and length, the position and arrangement of amino acids are very important concerning peptide function. Moreover, GLWQKI sequence is highly crucial for the antimicrobial activity of Caerin 4 antimicrobial peptide family.

Obestatin improve spatial memory impairment in a rat model of fetal alcohol spectrum disorders via inhibiting apoptosis and neuroinflammation.

Clinical and experimental evidence have demonstrated that, use of alcohol during pregnancy can interrupt brain development. Alcohol-induced neurocognitive deficits in offspring's are involved with activation of oxidative-inflammatory cascade joined with extensive apoptotic neurodegeneration in different brain regions such as hippocampus. Obestatin is a newly discovered peptide with anti-inflammatory, antioxidant, activities in different animal models. In this study, we aimed to evaluate the protective effects of obestatin on alcohol-induced neuronal apoptosis and neuroinflammation in rat pups with postnatal ethanol exposure. Through intragastric intubation, ethanol (5/27 g/kg/day) was administered in male Wistar rat pups on postnatal days 2-10 (third trimester in humans). The animals received Obestatin (1 and 5 µg/kg, S.C.) on postnatal days 2-10. Thirty-six days after birth, the spatial memory test was performed using Morris water maze test, and then, antioxidant enzymes and TNF-α levels were measured by ELISA assay. The expression level of GFAP and caspase-3 proteins was determined via immunohistochemical staining after the behavioral test. Obestatin significantly improved spatial memory deficits (P < .01), and obestatin treatment could significantly increase glutathione and total superoxide dismutase activity (P < .05), reduce level of malondialdehyde (P < .05) and TNF-α in comparison with the ethanol group (P < .01). It's also reduced caspase-3 level, and decreased GFAP-positive cells in the hippocampus of ethanol-exposed rat pups (P < .01). The result of this study shows the potential involvement of oxidative-inflammatory cascade-mediated apoptotic signaling in cognitive deficits due to postnatal ethanol exposure, the results also indicated the neuroprotective effects of Obestatin on alcohol-related behavioral, biochemical and molecular deficits.

Effects of Olive Leaf Extract on Prevention of Molecular, Histopathological, and Enzymatic Changes in Chicken Carbon Tetrachloride-Induced Liver Damage.

BACKGROUND: Today, the use of additives such as antibiotics and growth hormones that increase production efficiency in breeding broiler chickens has become inevitable. However, the use of such additives and antibiotics associated with side effects such as liver damage. Oxidative stress occurs due to an imbalance between oxidants and antioxidants. Studies have shown that olive leaves have an antioxidant effect on free radicals. This study was to evaluate the possible effect of olive leaf extract on carbon tetrachloride (CCL4)-induced liver damage (molecular and tissue) and changes of enzymes in chickens. MATERIALS AND METHODS: A total of 50 chickens were used and classified into5 groups. Treatment groups received 0.5, 1, and 1.5 mg/kg of the olive leaf extract from day 21 of the experiment. Two control groups-healthy and poisoned-did not receive any extract. On the day 35 of the experiment, 1cc of CCL4 was dissolved with olive oil and injected intraperitoneally into the experimental and poisoned control groups. Blood and liver tissue sampling were performed. RESULTS: The histopathology results showed that at high doses of olive leaf extract, the cells and vessels were regularly curable, and sinusoids were healthy. The expression of B-cell lymphoma 2 (BCL2) increased, and that of BH3 interacting domain death agonist (BID )decreased. Enzymatic tests, including serum glutamic-oxaloacetic transaminase, serum glutamic-pyruvic transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, showed a reduction in BID expression in the experimental group compared with the control group(P<0.005). CONCLUSION: We concluded that olive leaf extract boosts the BCL2 -an antiapoptotic gene-and reduces BID -an apoptosis gene-in the liver of chicken. It prevents the liver cells from disintegrating and destroys sinusoids and liver blood vessels. The high doses of the olive leaf extract caused liver resistance to CCL4 toxicity in chicken.

Crocin Inhibits Apoptosis and Astrogliosis of Hippocampus Neurons Against Methamphetamine Neurotoxicity via Antioxidant and Anti-inflammatory Mechanisms.

Methamphetamine (METH) is a stimulant drug, which can cause neurotoxicity and increase the risk of neurodegenerative disorders. The mechanisms of acute METH intoxication comprise intra-neuronal events including oxidative stress, dopamine oxidation, and excitotoxicity. According to recent studies, crocin protects neurons by functioning as an anti-oxidant, anti-inflammatory, and anti-apoptotic compound. Accordingly, this study aimed to determine if crocin can protect against METH-induced neurotoxicity. Seventy-two male Wistar rats that weighed 260-300 g were randomly allocated to six groups of control (n = 12), crocin 90 mg/kg group (n = 12), METH (n = 12), METH + crocin 30 mg/kg (n = 12), METH + crocin 60 mg/kg (n = 12), and METH + crocin 90 mg/kg (n = 12). METH neurotoxicity was induced by 40 mg/kg of METH in four injections (e.g., 4 × 10 mg/kg q. 2 h, IP). Crocin was intraperitoneally (IP) injected at 30 min, 24 h, and 48 h after the final injection of METH. Seven days after METH injection, the rats' brains were removed for biochemical assessment using the ELISA technique, and immunohistochemistry staining was used for caspase-3 and glial fibrillary acidic protein (GFAP) detection. Crocin treatment could significantly increase superoxide dismutase (P < 0.05) and glutathione (P < 0.01) levels and reduce malondialdehyde and TNF-α in comparison with the METH group (P < 0.05). Moreover, crocin could significantly decline the level of caspase-3 and GFAP-positive cells in the CA1 region (P < 0.01). According to the results, crocin exerts neuroprotective effects on METH neurotoxicity via the inhibition of apoptosis and neuroinflammation.

Stress during first pregnancy increases seizure threshold in adult male offspring.

OBJECTIVE(S): Stress induces many homeostatic aberrations which are followed by lifelong allostatic responses. Epilepsy is developed or influenced by different environmental factors, i.e. prenatal stress which makes many contradictory developmental changes in seizure threshold and intensity. We investigated the potential seizure response of the rat offspring to prenatal stress; the stress which was applied to their mothers. MATERIALS AND METHODS: Nine day heterogeneous sequential stress (HSS) model was used before and during the first and before the second pregnancy. The kindling was induced using 13 IP injections of pentylenetetrazol (PTZ) every 48 hr to adult male Wistar rat's offspring. RESULTS: The results of the present study demonstrated that, before pregnancy stress decreased the rate of kindling (P<0.05) in the offspring, while stress which was applied during pregnancy completely prevented kindling (P <0.001). Further, their convulsive latency was increased and tonic clonic seizure duration was decreased. In contrast, previous pregnancy and between pregnancies stress could not change kindling process. Although maternal separation stress did not change kindling development, it could increase convulsive intensities by elongating the duration of seizures (P<0.05) and reducing convulsion latency (P <0.05). CONCLUSION: It is concluded that stress detrimental effects could be prevented by stress which was applied around first pregnancy; however this beneficial effect is weakened by before second pregnancy stress.