The folic acid endophenotype and depression in an elderly population

Zhi-Zi-Chi Decoction Reverses Depressive Behaviors in CUMS Rats by Reducing Oxidative Stress Injury Via Regulating GSH/GSSG Pathway

Depression is one of the main diseases that lead to disability and loss of ability to work. As a traditional Chinese medicine, Zhi-zi-chi decoction is utilized to regulate and improve depression. However, the research on the antidepressant mechanism and efficacy material basis of Zhi-zi-chi decoction has not been reported yet. Our previous research has found that Zhi-Zi-chi decoction can reduce glutamate-induced oxidative stress damage to PC 12 cells, which can exert a neuroprotective effect, and the antidepressant effect of Zhi-Zi-chi decoction was verified in CUMS rat models. In this study, the animal model of depression was established by chronic unpredictable mild stimulation combined with feeding alone. The brain metabolic profile of depressed rats was analyzed by the method of metabolomics based on ultra-performance liquid chromatography-quadrupole/time-of-flight mass. 26 differential metabolites and six metabolic pathways related to the antidepressant of Zhi-zi-chi decoction were screened and analyzed. The targeted metabolism of the glutathione metabolic pathway was analyzed. At the same time, the levels of reactive oxygen species, superoxide dismutase, glutathione reductase, glutathione peroxidase in the brain of depressed rats were measured. Combined with our previous study, the antioxidant effect of the glutathione pathway in the antidepressant effect of Zhi-zi-chi decoction was verified from the cellular and animal levels respectively. These results indicated that Zhi-zi-chi decoction exerted a potential antidepressive effect associated with reversing the imbalance of glutathione and oxidative stress in the brain of depressed rats.

Assessing the diet quality of individuals with rheumatic conditions: a cross-sectional study

Arthritis is a significant cause of chronic pain and disability, affecting around 3.5 million Australians. However, little is known regarding the overall diet quality of those living with arthritis. This study aimed to assess the dietary quality of Australians living in the Australian Capital Territory region with arthritis. This cross-sectional study analysed dietary intake data of individuals living with arthritis using a validated food frequency questionnaire. Dietary quality was assessed using the Healthy Eating Index-2015 (HEI-2015) to examine associations between diet composition, age, income and arthritis impact using the short form of the Arthritis Impact Measurement Scales 2 (AIMS2-SF). Participants, predominantly female (82.6%), were grouped by age: 18-50 years (n = 32), 50-64 years (n = 31), and 65 + years (n = 23). Significant correlations were observed between age and HEI-2015 (r_s = 0.337, p = 0.002) and income and AIMS2-SF (r_s = - 0.353, p < 0.001). The mean HEI-2015 score for the 18-49 years group was fair (72.1 ± 12.3), lower than both the 50-64 years group score of good (81.5 ± 9.72) (p = 0.004), and the 65 + years group score of good (81.8 ± 12.1) (p = 0.007). Dietary fibre, seafood and plant protein, fatty acids, and refined grains were identified as dietary components of concern for the 18-49 years group, and total fruit and added sugar were components of concern for people in the worst tertile for the AIMS2-SF. People aged between 18 and 49 years are consuming a lower quality diet compared to people aged 50 years and over. Further research is needed to understand why this association is occurring in this high socioeconomic region of Australia (a high-income country).

Relationship Between B-Vitamin Biomarkers and Dietary Intake with Apolipoprotein E є4 in Alzheimer's Disease

The potential for B-vitamins to reduce plasma homocysteine (Hcy) and reduce the risk of Alzheimer's disease (AD) has been described previously. However, the role of Apolipoprotein E є4 (APOE4) in this relationship has not been adequately addressed. This case-control study explored APOE4 genotype in an Australian sample of 63 healthy individuals (female = 38; age = 76.9 ± 4.7 y) and 63 individuals with AD (female = 35, age = 77.1 ± 5.3 y). Findings revealed 55 of 126 participants expressed the APOE4 genotype with 37 of 126 having both AD and the APOE4 genotype. Analysis revealed an increased likelihood of AD when Hcy levels are >11.0 µmol/L (p = 0.012), cysteine levels were <255 µmol/L (p = 0.033) and serum folate was <22.0 nmol/L (p = 0.003; in males only). In females, dietary intake of total folate <336 µg/day (p=0.001), natural folate <270 µg/day (p = 0.011), and vitamin B2 < 1.12 mg/day (p = 0.028) was associated with an increased AD risk. These results support Hcy, Cys, and SF as useful biomarkers for AD, irrespective of APOE4 genotype and as such should be considered as part of screening and managing risk of AD.

Shared Genetic Risk Factors for Late-Life Depression and Alzheimer's Disease

BACKGROUND

Considerable evidence has been reported for the comorbidity between late-life depression (LLD) and Alzheimer's disease (AD), both of which are very common in the general elderly population and represent a large burden on the health of the elderly. The pathophysiological mechanisms underlying the link between LLD and AD are poorly understood. Because both LLD and AD can be heritable and are influenced by multiple risk genes, shared genetic risk factors between LLD and AD may exist.

OBJECTIVE

The objective is to review the existing evidence for genetic risk factors that are common to LLD and AD and to outline the biological substrates proposed to mediate this association.

METHODS

A literature review was performed.

RESULTS

Genetic polymorphisms of brain-derived neurotrophic factor, apolipoprotein E, interleukin 1-beta, and methylenetetrahydrofolate reductase have been demonstrated to confer increased risk to both LLD and AD by studies examining either LLD or AD patients. These results contribute to the understanding of pathophysiological mechanisms that are common to both of these disorders, including deficits in nerve growth factors, inflammatory changes, and dysregulation mechanisms involving lipoprotein and folate. Other conflicting results have also been reviewed, and few studies have investigated the effects of the described polymorphisms on both LLD and AD.

CONCLUSION

The findings suggest that common genetic pathways may underlie LLD and AD comorbidity. Studies to evaluate the genetic relationship between LLD and AD may provide insights into the molecular mechanisms that trigger disease progression as the population ages.

B vitamin polymorphisms and behavior: evidence of associations with neurodevelopment, depression, schizophrenia, bipolar disorder and cognitive decline

The B vitamins folic acid, vitamin B12 and B6 are essential for neuronal function, and severe deficiencies have been linked to increased risk of neurodevelopmental disorders, psychiatric disease and dementia. Polymorphisms of genes involved in B vitamin absorption, metabolism and function, such as methylene tetrahydrofolate reductase (MTHFR), cystathionine β synthase (CβS), transcobalamin 2 receptor (TCN2) and methionine synthase reductase (MTRR), have also been linked to increased incidence of psychiatric and cognitive disorders. However, the effects of these polymorphisms are often quite small and many studies failed to show any meaningful or consistent associations. This review discusses previous findings from clinical studies and highlights gaps in knowledge. Future studies assessing B vitamin-associated polymorphisms must take into account not just traditional demographics, but subjects' overall diet, relevant biomarkers of nutritional status and also analyze related genetic factors that may exacerbate behavioral effects or nutritional status.

Association analysis of COMT/MTHFR polymorphisms and major depressive disorder in Chinese Han population

BACKGROUND

In several previous biochemical and genetic studies, the Val158Met polymorphism of the gene encoding catechol-O-methyltransferase (COMT) and the C677T polymorphism of Methylenetetrahydrofolate reductase (MTHFR) have been suggested to be involved in the pathogenesis as well as the treatment response of major depressive disorder (MDD), but the results have been inconsistent. In this study, we investigate the association of COMT/MTHFR and their interactions with MDD and antidepressant response in Chinese Han population.

METHODS

Three hundred and sixty eight depressed patients who met DSM-IV criteria for MDD were recruited for the study. Two hundred and nineteen normal controls were recruited from the local community. Patients and normal controls were genotyped for the functional COMT val158met and MTHFR C677T polymorphisms. Patients were characterized for clinical response to antidepressant treatment as measured by intra-individual changes of Hamilton Depression (HAMD-17) scores over 6 weeks.

RESULTS

The T allele (OR=1.81; CI95%=1.40-2.34, P<0.001) and C/T genotype (OR=3.66; CI95% =2.53-5.28, P<0.001) of MTHFR C677T were significantly different between case and control groups. The COMT Met/Val genotype was more common among depressed individuals than among controls (OR=1.52, CI95%=1.04-2.21, P=0.02).

LIMITATION

There is disequilibrium in age and sex between case and control groups. Though we control the two variables in the statistic analysis, to be more accurate, we need to increase sample size in further study.

CONCLUSION

Individuals with the genotype COMT Met/Val and MTHFR C/T have more probability of suffering from MDD. However, there is no association between gene polymorphism and treatment response.

A study examining depression in restless legs syndrome

BACKGROUND

Distress is known to occur in RLS subjects consequent to symptoms. However, studies regarding prevalence of depression in RLS are scarce. This study was conducted to find out prevalence of depression in RLS patients and to explore possible underlying factors.

METHOD

112 consecutive RLS subjects presenting to sleep-clinic were included in this study. History regarding RLS, depression and sleep-disturbances was sought. Depression and insomnia were diagnosed using DSM-IV-TR criteria. Subjects were specifically asked whether they had depressive episodes in past one year. Severity of RLS and insomnia was measured using Hindi versions of IRLS and ISI, respectively. Family history of depression and RLS was also asked.

RESULTS

One year prevalence of depression was 41.8%. MDD was reported by 33% and dysthymia by 8.8%. Both the groups were comparable with respects to demographic and clinical features, viz., age, gender, duration, severity and family history of RLS. Duration, number of episodes and severity of insomnia were comparable between groups, so was the family history of depression. In 37.8% of the subjects with MDD, depressive symptoms preceded RLS while in 51.4% of them, they followed onset of RLS. Total duration of RLS symptoms did not correlate with total duration of depression (r(2)=0.07; P=0.64).

CONCLUSION

Clinical depression is seen in more than a third of RLS patients. Depression is not affected by clinical picture of RLS and it is not consequent to sleep disturbance. Perhaps, it is a co-morbid condition.

Serum folate is significantly correlated with plasma cysteine concentrations in healthy industry workers

BACKGROUND

A low concentration of serum folate is associated with an increased risk of cardiovascular disease. Extracellular cysteine is involved in aging, cancer and cardiovascular disease. The relationship between serum folate and plasma cysteine is poorly understood. Therefore, we investigated this relationship in industry workers, whose health has economic implications.

METHODS

The concentration of serum folate was determined by the Access ImmunoAssay System Sanofi Pasteur. Plasma cysteine and homocysteine were measured by an ion-pair HPLC method. The concentrations of serum triglycerides were determined by an enzymatic colorimetric method.

RESULTS

We detected a positive correlation between the concentration of serum folate and plasma cysteine, whereas the concentration of serum folate was negatively correlated with plasma homocysteine and serum triglycerides. In a multiple regression analysis with adjustment for age, BMI and smoking, serum folate as the dependent variable exhibited a strong relationship with plasma cysteine, and a negative relationship with plasma homocysteine and serum triglycerides.

CONCLUSION

We observed significant correlations between serum folate, plasma cysteine and serum triglyceride concentrations in industry workers, implying that folate may modulate key aspects of the body's cysteine and lipid metabolism.