Wideband PRM: Highly Accurate and Sensitive Method for High-Throughput Targeted Proteomics.

Targeted mass spectrometry (MS) approaches, which are powerful methods for uniquely and confidently quantifying a specific panel of proteins in complex biological samples, play a crucial role in validating and clinically translating protein biomarkers discovered through global proteomic profiling. Common targeted MS methods, such as multiple reaction monitoring (MRM) and parallel-reaction monitoring (PRM), employ specific mass spectrometric technologies to quantify protein levels by comparing the transitions of surrogate endogenous (ENDO) peptides with those of stable isotope-labeled (SIL) peptide counterparts. These methods utilizing amino acid analyzed (AAA) SIL peptides warrant sensitive and precise measurements required for targeted MS assays. Compared with MRM, PRM provides higher experimental throughput by simultaneously acquiring all transitions of the target peptides and thereby compensates for different ion suppressions among transitions of a target peptide. However, PRM still suffers different ion suppressions between ENDO and SIL peptides due to spray instability, as the ENDO and SIL peptides were monitored at different liquid chromatography (LC) retention times. Here we introduce a new targeted MS method, termed wideband PRM (WBPRM), that is designed for high-throughput targeted MS analysis. WBPRM employs a wide isolation window for simultaneous fragmentation of both ENDO and SIL peptides along with multiplexed single ion monitoring (SIM) scans for enhanced MS sensitivity of the target peptides. Compared with PRM, WBPRM was demonstrated to provide increased sensitivity, precision, and reproducibility of quantitative measurements of target peptides with increased throughput, allowing more target peptide measurements in a shortened experiment time. WBPRM is a straightforward adaptation to a manufacturer-provided MS method, making it an easily implementable technique, particularly in complex biological samples where the demand for higher precision, sensitivity, and efficiency is paramount.

Effect of protopanaxatriol saponin on spermatogenic stem cell survival in busulfan-treated male mice.

Background and aims: Panax ginseng C.A. Meyer is a medicinal herb widely used in Asian countries. Many of its pharmacological actions are attributed to ginsenosides (saponin). However, the pharmacological effects or functions of ginsenosides on mammalian spermatogenesis are unclear. Methods: In the present study study, we investigated the therapeutic and prophylactic effects of protopanaxatriol saponin (PT) on testicular organ weight and morphology, testicular germ cells, proliferation, differentiation and spermatogenesis after induction of toxicity by a chemotherapeutic agent, busulfan, in male mice. Results: Intraperitoneally (IP) busulfan treatment markedly decreased the organ weight of testis, caput and cauda epididymis. After the treatment, the testes had collapsed seminiferous tubules with incomplete spermatogenesis. However, a single dose of busulfan treatment followed by PT injection showed milder damage on seminiferous tubules than busulfan alone. Conclusion: These results suggest that PT is effective in recovery of the male reproductive organ, and induced an increase in the number and viability of germ cells overcoming busulfan toxicity. PT might have applications in the recovery of male infertility arising from azoospermia and oligospermia.

Egg yolk soluble protein stimulates the proliferation and differentiation of osteoblastic MC3T3-E1 cells.

We determined the effects of yolk water-soluble protein (YSP) on bone formation in pre-osteoblastic MC3T3-E1 cells. YSP (50-5,000 microg/ml) increased cell proliferation and collagen content. Alkaline phosphatase (ALP) activity was also increased by YSP treatment. After enhancement of ALP activity, significant augmentation of calcification was observed. These results suggest that YSP is a promising agent for the prevention and treatment of bone loss.