Circulating netrin-1 levels are reduced and related to corneal nerve fiber loss in patients with diabetic neuropathy.

AIMS/INTRODUCTION: Deficiency of neurotropic factors is implicated in diabetic neuropathy (DN). Netrin-1 is a neurotropic factor, but its association with DN has not been explored. We have assessed the association between serum netrin-1 levels and early diabetic neuropathy assessed by quantifying corneal nerve fiber loss using corneal confocal microscopy. MATERIALS AND METHODS: A total of 72 participants with type 2 diabetes, without and with corneal nerve fiber loss (DN- n = 42, DN+ n = 30), and 45 healthy controls were studied. Serum netrin-1 levels were measured by enzyme-linked immunosorbent assay, and corneal nerve morphology was assessed using corneal confocal microscopy. RESULTS: Corneal nerve fiber density, branch density, fiber length and serum netrin-1 levels were significantly lower in the DN- and DN+ groups compared with controls (P < 0.001). Netrin-1 levels correlated with corneal nerve fiber length in the DN+ group (r = 0.51; P < 0.01). A receiver operating characteristic curve analysis showed that a netrin-1 cut-off value of 599.6 (pg/mL) had an area under the curve of 0.85, with a sensitivity of 76% and specificity of 74% (P < 0.001; 95% confidence interval 0.76-0.94) for differentiating patients with and without corneal nerve loss. CONCLUSIONS: Serum netrin-1 levels show a progressive decline with increasing severity of small nerve fiber damage in patients with diabetes. Netrin-1 could act as a biomarker for small nerve fiber damage in DN.

Serum Chemerin Levels Correlate With Severity of Dysglycemia in Young Adult Women With Polycystic Ovary Syndrome.

Context: A subset of polycystic ovary syndrome (PCOS) individuals also have type 2 diabetes (T2D); an unmet need to identify this subgroup exists. Objective: We looked at the potential role of serum chemerin, a proinflammatory adipokine, in identifying dysglycemic PCOS. Methods: A total of 93 PCOS and 33 healthy controls were classified, based on fasting and 2-hour plasma glucose levels (2hPGPG) and glycated hemoglobin A1c (HbA1c) (%) into normoglycemic (n = 34), dysglycemic (n = 33), and T2D (n = 26). Serum chemerin were measured by enzyme-linked immunosorbent assay. Homeostatic model 2 assessment of insulin resistance (HOMA-2IR) and homeostatic model 2 assessment of ß-cell function (HOMA-2ß) were computed using serum C-peptide. Results: Metabolic syndrome was present in 9.7% (National Cholesterol Education Program) of PCOS. Waist circumference, body fat (%), 2hPGPG, and HbA1c levels were significantly higher in T2D group. Serum triglycerides/high-density lipoprotein cholesterol (TGs/HDL-c) ratio was increased in PCOS individuals with T2D; no significant changes in total cholesterol and LDL-c levels were seen. Serum chemerin levels were significantly higher (P < .001) in the PCOS group. Total body fat (%), 2hPGPG, HbA1c, and TG/HDL-c ratio correlated positively with chemerin levels. Serum chemerin levels correlated positively with HOMA2IR and negatively with HOMA-2ß. On receiver operating characteristic curve analysis, a serum chemerin cutoff level of greater than 309.3 ng/mL differentiated PCOS individuals with dysglycemia from those without (sensitivity 85.71%, specificity 89.47%). The Cohen kappa test revealed a substantial agreement (P < .001) between chemerin cutoff and 2hPGPG levels greater than 200 mg/dL. The present study is arguably the first ever to define a serum chemerin cutoff to distinguish PCOS individuals with T2D from those without. Conclusion: Elevated serum chemerin levels reliably identify PCOS individuals with dysglycemia. Further, longitudinal studies with larger samples are required to confirm this association.

Lipid-induced alteration in retinoic acid signaling leads to mitochondrial dysfunction in HepG2 and Huh7 cells.

A surfeit of mitochondrial reactive oxygen species (ROS) and inflammation serve as obligatory mediators of lipid-associated hepatocellular maladies. While retinoid homeostasis is essential in restoring systemic energy balance, its role in hepatic mitochondrial function remains elusive. The role of lecithin-retinol acyltransferase (LRAT) in maintenance of retinoid homeostasis is appreciated earlier; however, its role in modulating retinoic acid (RA) bioavailability upon lipid-imposition is unexplored. We identified LRAT overexpression in high-fat diet (HFD)-fed rats and palmitate-treated hepatoma cells. Elevation in LRAT expression depletes RA production and deregulates RA signaling. This altered RA metabolism enhances fat accumulation, accompanied by inflammation that leads to impaired mitochondrial function through enhanced ROS generation. Hence, LRAT inhibition could be a novel approach preventing lipid-induced mitochondrial dysfunction in hepatoma cells.

Trimester-Specific Reference Intervals for Thyroid Function Parameters in Indian Pregnant Women during Final Phase of Transition to Iodine Sufficiency.

BACKGROUND: Interpretation of thyroid function tests during pregnancy depends on gestational age, method, and population-specific reference intervals. Therefore, there is a worldwide trend to establish trimester-specific levels for different populations. The aim of this study was to establish a trimester-specific reference range for thyroid function parameters during pregnancy in Indian women. MATERIALS AND METHODS: Thyroid function tests (TSH, FT4, TT4, TT3) of 80, 76, and 73 women at 1st, 2nd, and 3rd trimester, respectively, and 168 nonpregnant women were analyzed after exclusion of low UIC(<150 µg/L) and anti-TPO positivity(>35 IU/ml). Urinary iodine excretion (UIC) was assessed in all. The 2.5th and 97.5th percentile values were used to determine the reference ranges for thyrotropin (TSH), free thyroxine (FT4), total thyroxine (TT4), and total triiodothyronine (TT3) for each trimester of pregnancy. RESULTS: The reference range for TSH for first trimester was 0.19-4.34 µIU/ml, for second trimester 0.46-4.57 µIU/ml, and for third trimester 0.61-4.62 µIU/ml. The reference range during three trimesters for FT4 (ng/dl) was 0.88-1.32, 0.89-1.60, and 0.87-1.54, for total T4 (µg/dl) was 5.9-12.9, 7.4-15.2, and 7.9-14.9. In nonpregnant women, FT4 was 0.83-1.34, total T4 was 5.3-11.8, and TSH was 0.79-4.29. The mean UIC in nonpregnant women was 176 ± 15.7 µg/L suggesting iodine-sufficiency in the cohort. CONCLUSION: The trimester-specific TSH range in pregnant women in this study is not significantly different from nonpregnant reference range in the final phase of transition to iodine sufficiency in India.

DBC1, p300, HDAC3, and Siah1 coordinately regulate ELL stability and function for expression of its target genes.

Among all of the Super Elongation Complex (SEC) components, ELL1 (also known as ELL) is the only bona fide elongation factor that directly stimulates transcription elongation by RNA polymerase II. However, the mechanism(s) of functional regulation of ELL1 (referred to as ELL hereafter), through its stabilization, is completely unknown. Here, we report a function of human DBC1 in regulating ELL stability involving HDAC3, p300, and Siah1. Mechanistically, we show that p300-mediated site-specific acetylation increases, whereas HDAC3-mediated deacetylation decreases, ELL stability through polyubiquitylation by the E3 ubiquitin ligase Siah1. DBC1 competes with HDAC3 for the same binding sites on ELL and thus increases its acetylation and stability. Knockdown of DBC1 reduces ELL levels and expression of a significant number of genes, including those involved in glucose metabolism. Consistently, Type 2 diabetes patient-derived peripheral blood mononuclear cells show reduced expression of DBC1 and ELL and associated key target genes required for glucose homeostasis. Thus, we describe a pathway of regulating stability and functions of key elongation factor ELL for expression of diverse sets of genes, including ones that are linked to Type 2 diabetes pathogenesis.

Thyroid Status in Patients with Type 2 Diabetes Attending a Tertiary Care Hospital in Eastern India.

OBJECTIVE: Type 2 diabetes mellitus and thyroid dysfunction (TD) are two major public health endocrine problem, but the prevalence of TD and iodine status in patients with T2 DM in India is less studied. The study objective was to explore the prevalence of TD and to evaluate iodine health in type 2 diabetes patients attending a tertiary care center in Eastern India. METHODS: Consecutive 100 patients with diabetes attending outpatient department were evaluated clinically and biochemically (thyrotropin [TSH], free thyroxine, anti-TPO antibody, and urinary iodine). We excluded pregnant women or patients taking drugs that can alter thyroid function. Subclinical hypothyroid and overt hypothyroidism were diagnosed as per standard definitions. RESULTS: Out of 100 patients were analyzed, 51 (51%) were male. Mean (±standard deviation) age was 45.4 ± 11.2 years, body mass index 24.1 ± 4.28 kg/m2, and duration of diabetes 7.76 ± 5.77 years. The prevalence of subclinical hypothyroidism and overt hypothyroidism was 23/100 (23%) and 3/100 (3%), respectively. Thyroid autoantibody was positive in 13 (13.1%) patients. All patients were iodine sufficient. A trend toward increased neuropathy (r = 0.45) and nephropathy (r = -0.29) was associated with rising TSH. CONCLUSION: Almost one in four people living with diabetes are suffering from TD. Thus, routine screening should be implemented. Salt iodination program is a huge success in this part of the country.

Inflammation, oxidative stress, and higher expression levels of Nrf2 and NQO1 proteins in the airways of women chronically exposed to biomass fuel smoke.

The study was carried out to examine whether chronic exposure to smoke during daily household cooking with biomass fuel (BMF) elicits changes in airway cytology and expressions of Nrf2 (nuclear factor erythroid 2 [NF-E2]-related factor 2 [Nrf2]), Keap1 (Kelch-like erythroid-cell-derived protein with CNC homology [ECH]-associated protein 1), and NQO1 (NAD(P)H:quinone oxidoreductase 1) proteins in the airways. For this, 282 BMF-using women (median age 34 year) and 236 age-matched women who cooked with liquefied petroleum gas (LPG) were enrolled. Particulate matter with diameters of < 10 µm (PM10) and < 2.5 µm (PM2.5) were measured in indoor air with real-time laser photometer. Routine hematology, sputum cytology, Nrf2, Keap1, NQO1, and generation of reactive oxygen species (ROS) along with the levels of superoxide dismutase (SOD) and catalase were measured in both groups. PM10 and PM2.5 levels were significantly higher in BMF-using households compared to LPG. Compared with LPG users, BMF users had 32% more leukocytes in circulation and their sputa were 1.4-times more cellular with significant increase in absolute number of neutrophils, lymphocytes, eosinophils, and alveolar macrophages, suggesting airway inflammation. ROS generation was 1.5-times higher in blood neutrophils and 34% higher in sputum cells of BMF users while erythrocyte SOD was 31% lower and plasma catalase was relatively unchanged, suggesting oxidative stress. In BMF users, Keap1 expression was reduced, the percentage of AEC with nuclear expression of Nrf2 was two- to three-times more, and NQO1 level in sputum cell lysate was two-times higher than that of LPG users. In conclusion, cooking with BMF was associated with Nrf2 activation and elevated NQO1 protein level in the airways. The changes may be adaptive cellular response to counteract biomass smoke-elicited oxidative stress and inflammation-related tissue injury in the airways.

Thioredoxin interacting protein mediates lipid-induced impairment of glucose uptake in skeletal muscle.

Insulin resistance (IR) is an important determinant of type-2 diabetes mellitus (T2DM). Free fatty acids (FFAs) induce IR by various mechanisms. A surfeit of circulating FFA leads to intra-myocellular lipid accumulation that induces mitochondrial ROS generation and worsens IR. However, the molecular mechanisms behind are unclear. We identified thioredoxin interacting protein (TxNIP), which is overexpressed in T2DM, to be a promoter of ROS-induced IR. We observed upregulation of TxNIP upon palmitate treatment in skeletal muscle cells that led to ROS generation and Glut-4 downregulation resulting in impaired glucose-uptake. FFA-induced overexpression of TxNIP gene was mediated through the activation of its bona-fide trans activator, ChREBP. Further, Palmitate-induced impairment in AMPK-SIRT-1 pathway resulted in overexpression of ChREBP. While Fenofibrate, abrogated PA-induced TxNIP expression and ROS generation in skeletal muscle cells, Saroglitazar, a dual PPARα/γ-agonist, not only inhibited PA-induced TXNIP expression but also led to greater improvement in glucose uptake. Taken together, TxNIP appears to be an important factor in FFA-induced ROS generation and IR in skeletal muscle cells, which can be modulated for the management of this complex disorder.

Changes in RANKL and osteoprotegerin expression after chronic exposure to indoor air pollution as a result of cooking with biomass fuel.

The impact of indoor air pollution as a result of cooking with unprocessed biomass on membrane-bound and serum receptor activator of nuclear factor-kappa ligand 1 (RANKL), its soluble decoy receptor osteoprotegerin (OPG) and osteoclast precursor CD14(+) CD16(+) monocytes was investigated. Seventy-four pre-menopausal women from eastern India using biomass and 65 control women who cooked with cleaner liquefied petroleum gas were enrolled. PM10 and PM2.5 levels in their indoor air were measured with real-time aerosol monitors. The levels of membrane-bound RANKL on leukocytes and percentage CD14(+) CD16(+) monocytes in the subjects' blood were assayed by flow cytometry. Soluble RANKL and OPG in serum were measured by ELISA. The results showed that PM10 and PM2.5 levels were significantly higher in the indoor air of biomass-using households. Compared with the control women, the levels of CD4(+) and CD19(+) lymphocytes and circulating granulocytes with elevated levels of membrane-bound RANKL were higher in biomass users. The serum levels of RANKL were increased by 41% whereas serum OPG was reduced by 22% among biomass users. The absolute number of CD14(+) CD16(+) monocytes was significantly increased in biomass users than the control women. After controlling for potential confounders, PM10 and PM2.5 levels were found to be positively associated with leukocyte and serum RANKL and CD14(+) CD16(+) monocyte levels, but negatively with serum OPG. From these results, we can conclude that chronic exposure to biomass smoke increased membrane-bound and soluble RANKL and circulating osteoclast precursors but decreased OPG, suggesting an increased risk of bone resorption and consequent osteoporosis in biomass-exposed women of a child-bearing age. Copyright © 2015 John Wiley & Sons, Ltd.

Phytoremediation of parboiled rice mill wastewater using water lettuce (Pistia stratiotes).

Phytoremediation is an emerging technology applied for treatment of wastewater. It is a suitable option notably in developing countries as it is simple, sustainable and cost effective. In the present lab-based batch study the free floating aquatic plant water lettuce (Pistia stratiotes) is used for treatment of parboiled rice mill wastewater having low pH, high chemical oxygen demand (COD), nitrogen, and phosphate. In raw rice mill wastewater (undiluted) growth of water lettuce is found to be inhibited. Later on, two different dilution approaches (raw and facultative pond effluent 1:1; raw and tap water 1:1) are applied in order to effectively use this technology. In all cases a control (without plant) is maintained to compare the performance with the Aquatic Plant based Treatment (APT) system. In the APT system results reveal that removal of soluble COD (SCOD), ammoniacal nitrogen (NH4-N), nitrate nitrogen (NO3-N), and soluble phosphorus (sol. P) are upto 65%, 98%, 70%, and 65% respectively. The study highlights the efficacy of water lettuce in removing organics and nutrients from parboiled rice mill wastewater.

Platelet hyperactivity, neurobehavioral symptoms and depression among Indian women chronically exposed to low level of arsenic.

The prevalence of neurobehavioral symptoms (NBS) and depression has been investigated in premenopausal rural women of West Bengal, India enrolled from arsenic (As) endemic (groundwater As 11-50 µg/L; n = 342) and control areas (As level ≤ 10 µg/L; n = 312). The subjective symptoms questionnaire and Beck's 21-point depression inventory-II were used for the detection of NBS and depression, respectively. Platelet P-selectin expression was measured by flow cytometry, plasma neurotransmitter activity with high performance liquid chromatography and groundwater As level by atomic absorption spectroscopy. The As level in groundwater was 2.72 ± 1.18 µg/L in control and 28.3 ± 13.51 µg/L in endemic areas (p < 0.0001). Women residing in endemic areas demonstrated a higher prevalence of depressive symptoms (39.8 vs. 19.9%, p < 0.001) and anxiety (43.3 vs. 18.0% in control, p < 0.001), fatigue (68.4 vs. 23.4%, p < 0.0001), reduced sense of taste (15.8 vs. 4.5%, p<0.0001) and smell (14.9 vs. 5.8%, p < 0.001); burning sensation (36.8 vs. 5.4%, p < 0.0001) and tingling or numbness in the extremities (25.1 vs. 5.1%, p < 0.0001); and transient loss of memory (69.9 vs. 28.2%, p < 0.001). As-exposed women had 1.6-times more plasma epinephrine and norepinephrine (p < 0.05), 1.8-times higher level plasma serotonin with 28.9% lower intraplatelet serotonin (p < 0.05 for both), but their plasma dopamine level was not significantly different (p>0.05) from that of controls. Moreover, women from endemic areas had 2.3-times more P-selectin-expressing platelets in their circulation (p < 0.001). After controlling the potential confounders, chronic low level As (11-50 µg/L) exposure showed a positive association with the prevalence of neurobehavioral symptoms and depression among Indian women in their child-bearing age.

Increased oxidative DNA damage and decreased expression of base excision repair proteins in airway epithelial cells of women who cook with biomass fuels.

To investigate whether biomass burning causes oxidative DNA damage and alters the expression of DNA base excision repair (BER) proteins in airway cells, sputum samples were collected from 80 premenopausal rural biomass-users and 70 age-matched control women who cooked with liquefied petroleum gas. Compared with control the airway cells of biomass-users showed increased DNA damage in alkaline comet assay. Biomass-users showed higher percentage of cells expressing oxidative DNA damage marker 8-oxoguanine and lower percentages of BER proteins OGG1 and APE1 by immunocytochemical staining. Reactive oxygen species (ROS) generation was doubled and level of superoxide dismutase was depleted significantly among biomass-users. The concentrations of particulate matters were higher in biomass-using households which positively correlated with ROS generation and negatively with BER proteins expressions. ROS generation was positively correlated with 8-oxoguanine and negatively with BER proteins suggesting cooking with biomass is a risk for genotoxicity among rural women in their child-bearing age.

Chronic low-level arsenic exposure reduces lung function in male population without skin lesions.

OBJECTIVES: The respiratory effects of chronic low-level arsenic exposure from groundwater have been investigated in West Bengal, India. METHODS: The participants (834 non-smoking adult males) were subdivided in two groups: an arsenic-exposed group (n = 446, mean age 35.3 years) drinking arsenic-contaminated groundwater (11-50 µg/L) and a control group of 388 age-matched men drinking water containing <10 µg/L of arsenic. Arsenic in water samples was measured by atomic absorption spectroscopy. The prevalence of respiratory symptoms was documented by structured, validated questionnaire. Pulmonary function test (PFT) was assessed by portable spirometer. RESULTS: Compared with control, the arsenic-exposed subjects had higher prevalence of upper and lower respiratory symptoms, dyspnea, asthma, eye irritation and headache. Besides, 20.6% of arsenic-exposed subjects had lung function deficits (predominantly restrictive and combined types) compared with 13.6% of control (p < 0.05). A positive association was observed between arsenic concentration in drinking water and the prevalence of respiratory symptoms, while a negative association existed between arsenic level and spirometric parameters. CONCLUSIONS: The findings suggest that even low-level arsenic exposure has deleterious respiratory effects.

Reduction of DNA mismatch repair protein expression in airway epithelial cells of premenopausal women chronically exposed to biomass smoke.

Biomass burning is a major source of indoor air pollution in rural India. This study examined whether chronic inhalation of biomass smoke causes change in the DNA mismatch repair (MMR) pathway in the airway cells. For this, airway cells exfoliated in sputum were collected from 72 premenopausal nonsmoking rural women (median age 34 years) who cooked with biomass (wood, dung, crop residues) and 68 control women who cooked with cleaner fuel liquefied petroleum gas (LPG) for the past 5 years or more. The levels of particulate matters with diameters less than 10 and 2.5 µm (PM10 and PM2.5) in indoor air were measured by real-time aerosol monitor. Benzene exposure was monitored by measuring trans,trans-muconic acid (t,t-MA) in urine by high-performance liquid chromatography with ultraviolet detector. Generation of reactive oxygen species (ROS) and level of superoxide dismutase (SOD) in airway cells were measured by flow cytometry and spectrophotometry, respectively. Immunocytochemical assay revealed lower percentage of airway epithelial cells expressing MMR proteins mutL homolog 1 (MLH1) and mutS homolog 2 (MSH2) in biomass-using women compared to LPG-using controls. Women who cooked with biomass had 6.7 times higher level of urinary t,t-MA, twofold increase in ROS generation, and 31 % depletion of SOD. Indoor air of biomass-using households had three times more particulate matters than that of controls. ROS, urinary t,t-MA, and particulate pollution in biomass-using kitchen had negative correlation, while SOD showed positive correlation with MSH2 and MLH1 expression. It appears that chronic exposure to biomass smoke reduces MMR response in airway epithelial cells, and oxidative stress plays an important role in the process.

Chronic inhalation of biomass smoke is associated with DNA damage in airway cells: involvement of particulate pollutants and benzene.

This study examined whether indoor air pollution from biomass fuel burning induces DNA damage in airway cells. For this, sputum cells were collected from 56 premenopausal rural women who cooked with biomass (wood, dung, crop residues) and 49 age-matched controls who cooked with cleaner liquefied petroleum gas. The levels of particulate matters with diameters of less than 10 and 2.5 µm (PM(10) and PM(2.5)) in indoor air were measured using a real-time aerosol monitor. Benzene exposure was monitored by measuring trans,trans-muconic acid (t,t-MA) in urine by HPLC-UV. DNA damage was examined by alkaline comet assay in sputum cells. Generation of reactive oxygen species (ROS) and level of superoxide dismutase (SOD) in sputum cells were measured by flow cytometry and spectrophotometry, respectively. Compared with controls, biomass users had 4 times higher tail percentage DNA, 37% more comet tail length and 5 times more Olive tail moment (p < 0.001) in inflammatory and epithelial cells in sputum, suggesting extensive DNA damage. In addition, women who cooked with biomass had 6 times higher levels of urinary t,t-MA and 2-fold higher levels of ROS generation concomitant with 28% depletion of SOD. Indoor air of biomass-using households had 2-4 times more PM(10) and PM(2.5) than that of controls. After controlling potential confounders, positive association was found between DNA damage parameters, particulate pollution, urinary t,t-MA and ROS. Thus, long-term exposure to biomass smoke induces DNA damage in airway cells and the effect was probably mediated, at least in part, by oxidative stress generated by inhaled particulate matter and benzene.

Cooking with biomass increases the risk of depression in pre-menopausal women in India.

Cooking with biomass fuel, a common practice in rural India, is associated with a high level of indoor air pollution (IAP). The aim of this study was to investigate whether IAP from biomass burning increases the risk of depression. For this cross-sectional study, we enrolled a group of 952 women (median age 37 years) who cooked regularly with biomass and a control group of 804 age-matched women who cooked with cleaner fuel (liquefied petroleum gas). Depression was assessed using the second edition of Beck's depression inventory (BDI-II). Platelet P-selectin expression was assessed by flow cytometry and platelet serotonin was measured by ELISA. Particulate matter having diameter of less than 10 and 2.5 µm (PM(10) and PM(2.5), respectively) in indoor air was measured by real-time aerosol monitor. Carbon monoxide (CO) in exhaled breath was measured by CO monitor. Compared with the control group, women who cooked with biomass had a higher prevalence of depression and depleted platelet serotonin, suggesting altered serotonergic activity in the brain. In addition, P-selectin expression on platelet surface was up-regulated implying platelet hyperactivity and consequent risk of cardiovascular disease. Biomass-using households had increased levels of PM(10) and PM(2.5), and biomass users had elevated levels of CO in expired air. Controlling potential confounders, cooking with biomass was found to be an independent and strong risk factor for depression. IAP from cooking with biomass is a risk for depression among rural women in their child-bearing age.

Upregulation of AgNOR expression in epithelial cells and neutrophils in the airways and leukocytes in peripheral blood of women chronically exposed to biomass smoke.

OBJECTIVE: To evaluate the impact of indoor air pollution from biomass fuel use on ribosome biogenesis in airway cells and peripheral blood leukocytes using the argyrophilic nucleolar organizer region (AgNOR) staining technique. STUDY DESIGN: Biomass users were represented by 78 never-smoking, premenopausal women from rural India and a control group of 73 age-matched women who cooked with liquefied petroleum gas (LPG). For silver staining, exfoliated airway cells and circulating lymphocytes and neutrophils were obtained from expectorated sputum and venous blood smears, respectively. Particulate pollution in indoor air was measured by real-time aerosol monitor. RESULTS: Compared with the controls, a statistically significant increase was observed in mean number of AgNOR dots per nucleus, their size, and the percentage of NOR-occupied nuclear area in exfoliated airway epithelial cells, airway neutrophils, and circulating lymphocytes and neutrophils of biomass users. Biomass-using households had 2 to 4 times more particulate pollutants than that of LPG-using households; the changes in AgNOR expression, especially in proliferating basal cells, were positively associated with PM10 and PM2.5 levels in indoor air after controlling potential confounders such as age, kitchen location, and family income. CONCLUSION: Indoor air pollution from biomass fuel use upregulates ribosome biogenesis in both the airways and peripheral blood.

Indoor air pollution from biomass burning activates Akt in airway cells and peripheral blood lymphocytes: a study among premenopausal women in rural India.

Biomass burning is a major source of indoor air pollution in rural India. The authors investigated in this study whether cumulative exposures to biomass smoke cause activation of the serine/threonine kinase Akt in airway cells and peripheral blood lymphocytes (PBL). For this, the authors enrolled 87 premenopausal (median age 34 years), nonsmoking women who used to cook with biomass (wood, dung, crop wastes) and 85 age-matched control women who cooked with cleaner fuel liquefied petroleum gas. Immunocytochemical and immunoblotting assays revealed significantly higher levels of phosphorylated forms of Akt protein (p-Akt(ser473) and p-Akt(thr308)) in PBL, airway epithelial cells, alveolar macrophages, and neutrophils in sputum of biomass-using women than control. Akt activation in biomass users was associated with marked rise in generation of reactive oxygen species and concomitant depletion of superoxide dismutase. Measurement of particulate matter having a diameter of less than 10 and 2.5 µm in indoor air by real-time aerosol monitor showed 2 to 4 times more particulate pollution in biomass-using households, and Akt activation was positively associated with particulate pollution after controlling potential confounders. The findings suggest that chronic exposure to biomass smoke activates Akt, possibly via generation of oxidative stress.

Micronucleus formation, DNA damage and repair in premenopausal women chronically exposed to high level of indoor air pollution from biomass fuel use in rural India.

Genotoxicity of indoor air pollution from biomass fuel use has been examined in 132 biomass users (median age 34 years) and 85 age-matched control women from eastern India who used the cleaner fuel liquefied petroleum gas (LPG) to cook. Micronucleus (MN) frequency was evaluated in buccal (BEC) and airway epithelial cells (AEC); DNA damage was examined by comet assay in peripheral blood lymphocytes (PBL); and expressions of gamma-H2AX, Mre11 and Ku70 proteins were localized in AEC and PBL by immunocytochemistry. Reactive oxygen species (ROS) generation in leukocytes was measured by flow cytometry, and the levels of superoxide dismutase (SOD) and total antioxidant status (TAS) in blood were measured by spectrophotometry. Real-time aerosol monitor was used to measure particulate pollutants in indoor air. Compared with controls, biomass users had increased frequencies of micronucleated cells in BEC (3.5 vs. 1.7, p<0.001) and AEC (4.54 vs. 1.86, p<0.001), and greater comet tail % DNA (18.6 vs. 11.7%, p<0.01), tail length (45.5 vs. 31.4mum, p<0.01) and olive tail moment (4.0 vs. 1.4, p<0.01) in PBL. Moreover, biomass users had more gamma-H2AX-positive nuclei in PBL (49.5 vs. 8.5%, p<0.01) and AEC (11.3 vs. 2.9%, p<0.01) along with higher expression of DNA repair proteins Mre11 and Ku70 in these cells, suggesting stimulation of DNA repair mechanism. Biomass users showed rise in ROS generation and depletion of SOD and TAS. Biomass-using households had 2-4 times more particulate matter with diameter less than 10 and 2.5mum in indoor air, and MN frequency and comet tail % DNA were positively associated with these pollutants after controlling potential confounders. Thus, chronic exposure to biomass smoke causes chromosomal and DNA damage and upregulation of DNA repair mechanism.