Examination of Surfactant Protein D as a Biomarker for Evaluating Pulmonary Toxicity of Nanomaterials in Rat

Abstract

This work studies the relationship between lung inflammation caused by nanomaterials and surfactant protein D (SP-D) kinetics and investigates whether SP-D can be a biomarker of the pulmonary toxicity of nanomaterials. Nanomaterials of nickel oxide and cerium dioxide were classified as having high toxicity, nanomaterials of two types of titanium dioxides and zinc oxide were classified as having low toxicity, and rat biological samples obtained from 3 days to 6 months after intratracheal instillation of those nanomaterials and micron-particles of crystalline silica were used. There were different tendencies of increase between the high- and low-toxicity materials in the concentration of SP-D in bronchoalveolar-lavage fluid (BALF) and serum and in the expression of the SP-D gene in the lung tissue. An analysis of the receiver operating characteristics for the toxicity of the nanomaterials by SP-D in BALF and serum showed a high accuracy of discrimination from 1 week to 3 or 6 months after exposure. These data suggest that the differences in the expression of SP-D in BALF and serum depended on the level of lung inflammation caused by the nanomaterials and that SP-D can be biomarkers for evaluating the pulmonary toxicity of nanomaterials.

Pulmonary disorder induced by cross-linked polyacrylic acid

“…On the other hand, SP‐D is a secreted protein produced by type II alveolar epithelial cells and club cells, 26 so their persistently elevated levels in BALF indicate that type II alveolar epithelial cells are under sustained stimulation. 27 The HE‐stained images of the pathology in this study showed hyperplasia of type II alveolar epithelium‐like cells peaking at 3 days after intratracheal instillation, and the hyperplasia persisted although DAD reduction was also reduced, suggesting that SP‐D may be produced from these increased alveolar epithelial cells. The difference in persistence of ALP and SP‐D may have been due to the former's release due to injury and the latter's release due to injury and the increase in cells produced by the repair process after that injury.…”

“…The pathological finding in the lungs is DAD, which peaks after 3 days and then declines, consistent with the trend of ALP. On the other hand, SP‐D is a secreted protein produced by type II alveolar epithelial cells and club cells, 26 so their persistently elevated levels in BALF indicate that type II alveolar epithelial cells are under sustained stimulation 27 . The HE‐stained images of the pathology in this study showed hyperplasia of type II alveolar epithelium‐like cells peaking at 3 days after intratracheal instillation, and the hyperplasia persisted although DAD reduction was also reduced, suggesting that SP‐D may be produced from these increased alveolar epithelial cells.…”

Inhalation Injury

“…The latest technologies allowing noninvasive measurement of carboxyhemoglobin using pulse CO-oximeter can be used at the site of injury for early diagnosis of inhalation injury. 12…”

“…Additionally, blood gas analysis, carboxyhemoglobin levels, and biomarkers such as surfactant protein-D may aid in assessing the severity and progression of inhalation injury. 12 Despite large amount of clinical and basic science research studies being published, there is no consensus on the diagnostic criteria for inhalation injury. It differs between the burn centers and hospitals.…”

Mechanisms of Nanotoxicology and the Important Role of Alternative Testing Strategies

“…The intratracheal instillation of high-toxicity (nickel oxide and cerium dioxide) and low-toxicity (titanium dioxides and zinc oxide) nanomaterials was conducted and rat biological samples (blood and BALF) taken from 3 days to 6 months after installation were collected. The results indicated that the expression of SP-D in serum and BALF depended on the level of lung inflammation and that SP-D can serve as a biomarker for evaluating the pulmonary toxicity of nanomaterials [ 10 ]. Another study investigated the impact of copper-titanium dioxide nanocomposite (Cu/TiO 2 -NC) on bacteria viability, antioxidant enzymes, and fatty acid profiling.…”