Page 51 - Biennial Report 2018-20 Jun 2021

international standards, but normal by Indian standards, are much more likely to have clinically
significant elevation of IL8 or TNF-α, as compared to those who are normal by international
standards. Shorter and thinner children showed poorest z scores for lung function, after
accounting for height, weight, and gender, suggestive of nutritional stunting being important
along with possible gut dysbiosis as a cause of the low grade chronic inflammation. Data from
the Pune Birth Cohort suggested protein intake to be a potential factor and the early life head
circumference/length ratio to be an inverse predictor.

Biochemical parameters were estimated for additional 1000 subjects. The trends obtained by
reanalyzing data including the new data points were consistent with the previous findings. These
results confirm the negative association between inflammatory cytokines (IL8, TNF-α) and lung
function, adjusted for all other relevant parameters. A positive association was also observed
between haemoglobin levels and lung function.

DIESEL EXHAUST AND ITS IMPACT ON RESPIRATORY HEALTH

Diesel exhaust has proved to be major contributor of urban air pollution contributing 28% of the
PM. Therefore, the group led by Naveen Arora is studying molecular aspect of diesel exhaust
exposure (DEE) on lung health and disease phenotype associated with its exposure.
Present analysis of the murine model of diesel exhaust exposure has shown decremental effect
on lung health. DEE significantly increases total and differential cell count (macrophages, mono-
nuclear and neutrophil) compared to control. Accumulation of particulate matter and carbon-
laden macrophages were seen in the cells. Cytokine analysis showed increased expression of
proinflammatory cytokines IL-6 & TNF-α. IL-17A and TGF-β (profibrotic) were significantly
increased in the mice exposed to DE. Lung histology showed thickening of bronchiolar wall and
infiltration of immune cells in bronchiolar and alveolar region. Relative expression of genes
involved in fibrosis i.e., α-SMA, Fibronectin and MMP-9 was significantly increased in lung tissue.
TGF-β downstream signaling genes like smad 3, smad 4 and snail 1 were also significantly
increased. miRNA profiling illustrated 30 differentially expressed miRNA, of which miR-145, miR-
29c and miR-30e were involved in tissue fibrosis. Future studies will involve in deciphering the
pathways involved in lung fibrosis along with oxidative & antioxidant imbalance involved in diesel
exhaust exposure.

SOLID WASTE DUMPING SITES AS CAUSE OF AIR POLLUTION AND CONSEQUENT
RESPIRATORY HEALTH RISKS

Studies on traffic policemen and in health camps for people living near solid waste dump sites
and engaged in occupation of waste disposal have shown surprising results. While pollution
levels on roads and at these sites are very high, there are no clear correlates with lung function.
Traffic policemen had better lung function than control subjects at all ages and showed lower
decline. This may be because of better health at the time of selection into the police. Locals living
near the dump for longer periods had better lung function than recent immigrants. Socio-
economic and other health determinants seem to be stronger predictors of lung function than
air pollution of gaseous or solid types.
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