Browsing by Author "Berardinelli, James G."

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Aging influences the response of T cells to stimulation by the ellagitannin, oenothein B
(2015-06) Ramstead, Andrew G.; Schepetkin, Igor A.; Todd, Kimberly; Loeffelholz, James; Berardinelli, James G.; Quinn, Mark T.; Jutila, Mark A.
Several plant extracts, including certain polyphenols, prime innate lymphocytes and enhance responses to secondary stimuli. Oenothein B, a polyphenol isolated from Epilobium angustifolium and other plant sources, enhances IFNÎ³ production by both bovine and human NK cells and T cells, alone and in response to secondary stimulation by cytokines or tumor cells. Innate immune cell responsiveness is known to be affected by aging, but whether polyphenol responses by these cells are also impacted by aging is not known. Therefore, we examined oenothein B responsiveness in T cells from cord blood, young, and adult donors. We found that oenothein B stimulates bovine and human T cells from individuals over a broad range of ages, as measured by increased IL-2RÎ± and CD69 expression. However, clear differences in induction of cytokine production by T cells were seen. In T cells from human cord blood and bovine calves, oenothein B was unable to induce IFNÎ³ production. However, oenothein B induced IFNÎ³ production by T cells from adult humans and cattle. In addition, oenothein B induced GM-CSF production by human adult T cells, but not cord blood T cells. Within the responsive T cell population, we found that CD45RO + memory T cells expressed more cytokines in response to oenothein B than CD45RO âˆ’ T cells. In summary, our data suggest that the immunostimulation of T cells by oenothein B is influenced by age, particularly with respect to immune cytokine production.
Temporal concentrations of cortisol and LH in virgin ewes acutely exposed to rams during the transition into the breeding season
(2015-03) McCosh, Richard B.; Berry, E. M.; Wehrman, M. E.; Redden, R. R.; Hallford, D. M.; Berardinelli, James G.
The objectives of this study were to determine if exposing seasonally anovular ewes to rams would alter patterns of cortisol concentrations, and if these changes are associated with changes in characteristics of LH concentrations. Seasonally anestrous ewes were assigned to be exposed to rams (RE; n = 11) or wethers (NE; n = 12). Blood samples were collected at 15-min intervals beginning 120 min before introduction of males (time = 0 min), and continued for 360 min after male exposure. Characteristics of cortisol and LH concentrations included: mean and baseline concentrations, pulse amplitude, duration, frequency, and time to first pulse. Mean and baseline cortisol concentrations, and cortisol pulse amplitude, frequency, and time to first pulse after male exposure did not differ between RE and NE ewes. Cortisol pulse duration was longer (P < 0.05) in RE ewes than in NE ewes. Mean LH and LH pulse amplitude, duration, and time to first pulse after male exposure did not differ between RE and NE ewes. Baseline LH concentrations and LH pulse frequency were greater (P < 0.05) in RE than in NE ewes. In RE ewes, but not NE ewes, LH pulse frequency tended to increase (P = 0.06) as pulse frequency of cortisol decreased. In conclusion, exposing ewes to mature rams during the transition into the breeding season increased LH pulse frequency which hastened ovulatory activity. However, the results do not support the hypothesis that changes in cortisol concentrations plays a significant role in the ‘ram effect’.