Effects of lipoic acid and n-3 long-chain polyunsaturated fatty acid on the liver ovariectomized rat model of menopause

The neuroprotective effects of alpha lipoic acid in rotenone-induced Parkinson's disease in mice via activating PI3K/AKT pathway and antagonizing related inflammatory cascades

Parkinson's disease (PD) is an idiopathic disease caused by the loss or degeneration of the dopaminergic (dopamine-producing) neurons in the brain and characterized by various inflammatory and apoptotic responses in the neuronal cells. Phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) axis is responsible for neuronal survival by providing a number of anti-inflammatory and anti-apoptotic milieu that prevent the progression of PD. Alpha-lipoic acid (ALA) is a natural cofactor that has antioxidant capacity and contributes to various metabolic processes. ALA can penetrate the blood-brain barrier and contribute to numerous neuroprotective effects. It can activate PI3K/AKT pathway with consequent reduction of different inflammatory and oxidative biomarkers. Our work aims to unfold the neuroprotective effects of ALA via targeting PI3k/AKT pathway. Forty male mice were divided into four groups: control, ALA (100 mg/kg/day; i.p.), rotenone (ROT) (1.5 mg/kg/2 days, i.p.) and rotenone + ALA for 21 days. ALA showed obvious neuroprotective effects via significant activation of PI3K/AKT pathway with subsequent decreasing level of Caspase-3. ALA resulted in prominent anti-inflammatory actions by decreasing interlukin-1β (IL-1β), tumor necrosis factor (TNF)-α and nuclear factor kabba (NFk)-B. ALA remarkably induced antioxidant activities via increasing reduced glutathione (GSH) and superoxide dismutase (SOD) levels as well as decreasing malondialdehyde (MDA) level. The substantial behavioral improvement reflected in these results was noticed in the ALA-treated mice as a reflection of the neuroprotective activities of ALA. In conclusion, ALA showed promising neuroprotective effects in rotenone-induced PD via activating the PI3K/AKT pathway and consequent inhibition of apoptotic and inflammatory biomarkers.

Improvement in Menopause-Associated Hepatic Lipid Metabolic Disorders by Herbal Formula HPC03 on Ovariectomized Rats

Postmenopausal women have an increased risk of developing nonalcoholic fatty liver disease (NAFLD). We formulated a combination of three herb mixtures (HPC03) and observed lipid-lowering efficacy. HepG2 cells were treated with oleic acid to induce an NAFLD model (in vitro). Also, we investigated potential of HPC03 in an ovariectomize- (OVX-) induced NAFLD model (in vivo). We separated the mice into six groups, as follows: SHAM, OVX, OVX + β-estradiol, and OVX + HPC03 (50, 100, and 200 mg/kg). Rats were administered with/without HPC03 for 12 weeks. HPC03 dose dependently inhibited the lipid accumulation involved in lipogenesis in HepG2 cells. The body weight, fat mass, and weights of the liver were decreased in the OVX group than that in the other groups. HPC03 had decreased adiposity that was induced by OVX. HPC03 treatment reduced liver lipid deposition and prevented the increase in serum and liver triglyceride export when there was a deficiency in estradiol. HPC03 improves OVX-induced fatty liver and lipid metabolism. These findings suggest that HPC03 from postmenopausal women has a protective effect during NAFLD conditions.

The Effects of Carob (Ceratonia siliqua L.) on Emotional Behavior Impairment and Metabolic Disorders Induced by Estrogen Deficiency in Rats

Carob (Ceratonia siliqua L.) contains a wide variety of polyphenols with high antioxidant properties. In this study, we investigated the effects of aqueous extract of carob pods (AECP) on emotional behavior impairments and metabolic disorders in ovariectomized (OVX) rats. Female Wistar rats were assigned to three groups: group 1, control non-OVX rats; group 2, OVX rats; and group 3, OVX rats orally treated with AECP (500 mg/kg) for15 days after ovariectomy. Elevated plus-maze and open-field tests were performed on the 26th and 27th post-ovariectomy days, respectively. Afterwards, the rats were anesthetized and their serums were collected for biochemical analysis. We found that AECP improved emotional behavior impairments revealed by elevated plus-maze and open-field tests in OVX rats. Moreover, ovariectomy significantly increased triglyceride, lactate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase levels in the serum. AECP administration significantly reversed ovariectomy-induced biochemical alterations. Thus, we suggest that the AECP may have an anxiolytic-like effect and prevent biochemical disorders associated with menopause or ovariectomy.

Protective Effects of α-Lipoic Acid on Vascular Oxidative Stress in Rats with Hyperuricemia

The aim of the present study was to observe the protective effects of α-lipoic acid (ALA) on vascular injury in rats with hyperuricemia (HUA). The ALA treatment groups (10, 30 and 90 mg/kg, respectively) were administered with ALA via gavage for 2 weeks. Subsequently, the levels of blood urea nitrogen (BUN), creatinine (CREA), uric acid (UA), total cholesterol (TC), high density lipoprotein-C (HDL-C) and low density lipoprotein-C (LDL-C) were measured; the activities of glutathione peroxidase (GSH-Px), catalase (CAT), malonaldehyde (MDA), superoxide dismutase (SOD) and xanthine oxidase (XOD) were also determined. The thoracic aorta of rats in each experimental group was observed under a light microscope; ultrastructural analysis was performed. SOD and CAT protein contents were investigated by Western blotting. The results revealed that: i) Compared with the model group, the levels of UA were decreased in the ALA groups and the levels of BUN, CREA, TC, and LDL-C decreased in the 30 and 90 mg/kg ALA groups (P<0.05); ii) compared with the model group, the activities of GSH-Px, SOD and XOD were increased and the levels of MDA were reduced in the 90 mg/kg ALA group (P&lt;0.05); and iii) in the model and 10 mg/kg ALA groups, edema and shedding were observed in endothelial cells. Compared with the model and 10 mg/kg ALA groups, the 30 and 90 mg/kg ALA groups exhibited fewer swollen endothelial cells. In summary, the results of the present study indicated that HUA resulted in vascular oxidative stress injury and decreased the activity of antioxidative enzymes, which leads to endothelial cell damage and vascular lesions. ALA may serve as a therapeutic agent for the treatment of HUA-induced endothelial dysfunction.

Effects of lipoic acid and ω-3 long-chain polyunsaturated fatty acids on the kidney in the ovariectomized rat model of menopause

OBJECTIVES

The loss of antioxidant protection from estrogen during menopause may lead to oxidative stress in the kidneys. Thus, antioxidant supplementation may potentially decrease the menopause-derived oxidative stress. The aim of this study was to evaluate the effect of α-lipoic acid (LA) and ω-3 long-chain polyunsaturated fatty acids on the redox profile of the kidneys in the ovariectomized rat model of menopause.

METHODS

We assessed oxidative damage markers and antioxidant defenses in the kidneys of ovariectomized rats supplemented with LA, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA). Animals received 3 mo of dietary supplementation.

RESULTS

Ovariectomy did not increase the levels of the damage markers carbonyl and malondialdehyde. EPA supplementation increased carbonyl and malondialdehyde levels. Ovariectomy increased fumarase activity but did not affect the levels of vitamin C, glutathione, and glutathione S-transferase activity. LA, DHA, and EPA supplementation decreased fumarase activity, but increased the levels of vitamin C, glutathione, and glutathione S-transferase activity. Vitamin E, superoxide dismutase, glutathione peroxidase, and peroxide consumption were not affected by ovariectomy or supplementation.

CONCLUSIONS

The results suggest that ovariectomy did not affect the redox profile in the kidneys. LA, DHA, and EPA supplementation increased certain endogenous antioxidants; however, EPA may have a prooxidant effect on the kidneys.

The effect of n-3 long-chain polyunsaturated fatty acids and lipoic acid on the heart in the ovariectomized rat model of menopause

Menopause occurs as consequence of ovarian senescence that leads to a drop of oestrogen hormone. The decreased oestrogen levels combined with the impairment of the redox system may contribute to the increased risk of postmenopausal cardiovascular disease. Supplementation with antioxidants may be an alternative to reduce cardiovascular risk. The study evaluated the effect of dietary supplementation with docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and α-lipoic acid (LA) for a period of 16 weeks on oxidative stress biomarkers in the hearts of ovariectomized 3-month-old rats. Ovariectomy did not increase the level of the damage markers malondialdehyde and carbonyl, and both were decreased by LA supplementation. Ovariectomy increased the levels of the endogenous antioxidants glutathione, vitamin C and H₂O₂ consumption, after restoration by DHA, EPA, and LA supplementation. Vitamin E, glutathione peroxidase, glutathione-S-transferase, and superoxide dismutase are not altered by ovariectomy. Lipid and protein damage are not increased after ovariectomy and a portion of the endogenous antioxidants concomitantly increased, suggesting that hearts may be protected by these antioxidants. DHA, EPA, and LA restored these endogenous antioxidants, showing that all evaluated supplements are effective in modulating the antioxidant redox system in the heart. LA showed additional effect on redox markers, decreasing lipid and protein damage markers.

Beneficial effects of Cirsium japonicum var. maackii on menopausal symptoms in ovariectomized rats

In women, menopause refers to a series of physiological and mental symptoms of distress that result from a decrease in 17β-estradiol. In addition to the loss of fertility, the symptoms include facial flushing, depression, osteoporosis, sexual dysfunction, and genitourinary atrophy. Cirsium japonicum var. maackii is a perennial herbaceous species found in the mountains and fields of Korea, China, and Japan. The medicinal uses of C. japonicum include antioxidant, antidiabetic, antitumor, antifungal, and anti-inflammatory activities. We investigated the effect of C. japonicum extract in a rat model of menopause that exhibited rapid estrogen decline induced by ovariectomy (OVX rats). The rats were treated with C. japonicum extract for 10 weeks and the following parameters were measured: food intake, feed efficiency, body weight, total cholesterol, triglyceride, LDL-cholesterol, HDL-cholesterol, liver weight, 17β-estradiol, uterus weight, AST, ALT, bone mineral density (BMD), bone alkaline phosphatase, calcitonin, and osteocalcin. In OVX rats, the administration of 50 and 100 mg kg-1C. japonicum extract significantly decreased body weight, total cholesterol, triglyceride, HDL-cholesterol, and LDL-cholesterol and significantly increased 17β-estradiol and BMD. During the light/dark box test, the C. japonicum treatment group (100 mg kg-1) spent more time in the light chamber than in the dark area, which was reflective of their diurnal nature. Using a molecular docking simulation, we predicted the plausible binding mode of the active compounds of C. japonicum with the ligand binding domain of estrogen receptor (ER)-α and ER-β. These results showed that C. japonicum extract can treat the symptoms before and after the menopause.

A New Approach to Treating Neurodegenerative Otologic Disorders

Hearing loss, the most common neurological disorder and the fourth leading cause of years lived with disability, can have profound effects on quality of life. The impact of this "invisible disability," with significant consequences, economic and personal, is most substantial in low- and middle-income countries, where >80% of affected people live. Given the importance of hearing for communication, enjoyment, and safety, with up to 500 million affected globally at a cost of nearly $800 billion/year, research on new approaches toward prevention and treatment is attracting increased attention. The consequences of noise pollution are largely preventable, but irreversible hearing loss can result from aging, disease, or drug side effects. Once damage occurs, treatment relies on hearing aids and cochlear implants. Preventing, delaying, or reducing some degree of hearing loss may be possible by avoiding excessive noise and addressing major contributory factors such as cardiovascular risk. However, given the magnitude of the problem, these interventions alone are unlikely to be sufficient. Recent advances in understanding principal mechanisms that govern hearing function, together with new drug discovery paradigms designed to identify efficacious therapies, bode well for pharmaceutical intervention. This review surveys various causes of loss of auditory function and discusses potential neurological underpinnings, including mitochondrial dysfunction. Mitochondria mitigate cell protection, survival, and function and may succumb to cumulative degradation of energy production and performance; the end result is cell death. Energy-demanding neurons and vestibulocochlear hair cells are vulnerable to mitochondrial dysfunction, and hearing impairment and deafness are characteristic of neurodegenerative mitochondrial disease phenotypes. Beyond acting as cellular powerhouses, mitochondria regulate immune responses to infections, and studies of this phenomenon have aided in identifying nuclear factor kappa B and nuclear factor erythroid 2-related factor 2/antioxidant response element signaling as targets for discovery of otologic drugs, respectively, suppressing or upregulating these pathways. Treatment with free radical scavenging antioxidants is one therapeutic approach, with lipoic acid and corresponding carnitine esters exhibiting improved biodistribution and other features showing promise. These compounds are also histone deacetylase (HDAC) inhibitors, adding epigenetic modulation to the mechanistic milieu through which they act. These data suggest that new drugs targeting mitochondrial dysfunction and modulating epigenetic pathways via HDAC inhibition or other mechanisms hold great promise.

Role of asthma and intolerance to acetylsalicylic acid on the redox profile in nasal polyp tissue

PURPOSE

Nasal polyposis is a chronic inflammatory disease of the mucosa of the nasal cavity and paranasal sinuses. The etiology of nasal polyposis is unclear; however, it may be associated with asthma and intolerance to acetylsalicylic acid, possibly altering the redox profile. The study intends to compare the redox profile in polyps surgically removed from three clinical groups of patients with nasal polyposis who were divided according to the presence of asthma and intolerance to acetylsalicylic acid.

METHODS

Patients were divided into three groups: nasal polyposis only (n = 30); nasal polyposis and asthma (n = 19); and nasal polyposis, asthma and intolerance to acetylsalicylic acid (n = 10). The following redox evaluations were performed: enzymatic antioxidant activity of superoxide dismutase, glutathione peroxidase, hydrogen peroxide consumption and glutathione S-transferase; non-enzymatic antioxidant levels of vitamin C, vitamin E and glutathione; levels of the oxidative damage biomarkers carbonyl groups (measuring protein damage) and malondialdehyde (measuring lipid peroxidation); and nitrite and nitrate levels.

RESULTS

Compared with the polyposis only group, hydrogen peroxide consumption, glutathione S-transferase, vitamin E and malondialdehyde were lower in the asthma group. Total glutathione (0.12 ± 0.01 vs. 33.34 ± 10.48 µmol/mg) and nitrite and nitrate (0.06 ± 0.01 vs. 15.95 ± 1.38 nmol/mg) levels were higher in the nasal polyposis, asthma and intolerance to acetylsalicylic acid group.

CONCLUSIONS

In patients with nasal polyposis, asthma may alter the redox profile associated with the hydrogen peroxide and lipid damage pathways, whereas asthma and intolerance to acetylsalicylic acid increase nitrite and nitrate and total glutathione levels.