Benefits on Hematological and Biochemical Parameters of a High-Intensity Interval Training Program for a Half-Marathon in Recreational Middle-Aged Women Runners

(1) Background: half-marathon races are popular among recreational runners, with increases in participation among middle-aged and women. We aimed to determine the effects of two half-marathon training programs on hematological and biochemical markers in middle-aged female recreational runners; (2) Methods: ten women (40 ± 7 years) followed moderate intensity continuous training (MICT), based on running volume below 80% V˙O2max, and another ten women followed high intensity interval training (HIIT) at 80%–100% V˙O2max, with less volume, and combined with eccentric loading exercise. Hematology, plasma osmolality, and plasma markers of metabolic status, muscle damage, inflammatory, and oxidative stress were measured before (S1) and after (S2) training and 24 h after the half-marathon (S3); (3) Results: both training programs had similar moderate effects at S2. However, the acute response at S3 induced different alterations. There was a greater decrease in cholesterol and triglyceride levels in MICT and reductions in markers of damage and inflammation in HIIT. Greater variability in some plasma markers at S3 in MICT suggests that there is inter-individual variability in the response to training; (4) Conclusions: HIIT led to better adaptation to the competition maybe because of the repeated exposure to higher oxygen consumption and eccentric loading exercise.

Primary adipsia and severe hypernatremia in a Pit Bull dog

ABSTRACT: Primary adipsia is a rare condition in which there is failure in the activation threshold of the hypothalamic osmoreceptors, leading to osmolality imbalance. Here, we reported the case of a Pit Bull dog with an altered level of consciousness (started after weaning) and adipsia. There was an increase in plasma osmolality (444 mOsm/kg), sodium (223.7 mg/dL), and chlorine (173 mg/dL) levels. Based on the suspicion of primary adipsia, water was administered via a nasogastric tube, with clinical improvement. The owner was instructed to supply water with food. Eight months after discharge, the dog returned with parvovirus and died. In the anatomopathological examination, no structural changes were observed in the central nervous system. To our knowledge, this is the first report of hypernatremia due to adipsia in a Pit Bull dog, showing that this is a differential diagnosis that should be considered in this breed.

Evaluation of Renal Function and Plasma Osmolality among Covid-19 Patients in Sudan

Objective: COVID-19 is a very serious disease and is considered a pandemic by the WHO. The aim of this study is to determine the renal function and serum osmolality among COVID-19 patients in Khartoum state, Sudan. Method: This is retrospective study was conducted in Gebra Hospital, Khartoum state, Sudan from April 2021 to August 2021. The study enrolled 50 patients with Covid-19 and 50 healthy individuals as a control group. After all the enrolled participants signed the informed consent the samples were analyzed for Creatinine, Urea, Sodium, and potassium. By using an A25 fully automated chemistry analyzer, and serum Osmolality (mOsm / kg) was calculated according to Smithline and Gardner formula. Results: The study revealed a significant increase of the mean of Urea (P.value = 0.001), Creatinine (P.value = 0.001), however significant decrease in the mean of e GFR (P.value<0.05) on the first day of the admission. There was a significant increase in the mean of plasma Urea, Creatinine, and eGFR on the 7th day of admission when compared with the first day, P.value = (0.0001), (0.001), (0.001), respectively. The study revealed a significant difference in plasma Osmolality in COVID-19 patients (280.73 ±16.10 mOsm/kg) when compared with the control group (288.13 ±3.42 mOsm/kg), P.value = 0.0. Conclusion: COVID-19 does not affect only the lungs; it can also affect the kidney. This study concluded that there were an elevated serum creatinine, blood urea, and low glomerular filtration, and there was a significant difference in serum osmolality in COVID- 19 than in the healthy group. Keywords: COVID -19; Serum Osmolality; eGFR; Renal function; Sudan.

MET-3 A Case of Intrapituitary Adenoma Metastasis from Advanced gastric cancer

Metastasis from extracranial tumor into a pituitary adenoma is a rare case. We report a case of metastasis from gastric cancer to a giant pituitary tumor. A 65-year-old man had been drinking more water and had an increased frequency of urine in 10 years. From that time, the patient was gradually aware of the pain in his left eye. In 20XX the patient had a sudden severe headache and pain of his eyes and visited an ophthalmologist. The patient was referred to our institution with general malaise and nausea, vomiting. A cerebral MRI disclosed Extensive neoplastic lesions from the base of the skull to the nasal cavity. The left eye had esotropia and abduction disorder. Laboratory test demonstrated hyponatremia (Na 126mEq/L) and decreased in plasma osmolality (273mOsm/kg), D-dimer, fibrinogen and CA19-9 were high level. One week after admission, the patient’s symptom was getting worse. The patient underwent FDG PET/CT, which showed FDG avid in the gastric wall and clivus tumor. The lesion was suspected gastric cancer and performed Esophagogastroduodenoscopy. The biopsy-based pathology was showed cubic and round cells with high NC ratio and signet-ring cells containing mucin. And clivus tumor was biopsied at an otolaryngologist because part of the tumor was exposed from the nasal cavity. The biopsy-based pathology was showed a small amount of adenocarcinoma cells which is surrounded by pituitary adenoma. The patient was diagnosed as intrapituitary adenoma metastasis from advanced gastric cancer and has been started radiation therapy. But the level of consciousness dropped sharply, so radiation therapy had become difficult to continue. The patient transferred to palliative care ward and died 3 months after his first visit. In this case, diagnosis and treatment were difficult due to the that the image was a finding a malignant tumor and the rapid progression of symptoms.

Apelin and Vasopressin: The Yin and Yang of Water Balance

Apelin, a (neuro)vasoactive peptide, plays a prominent role in controlling body fluid homeostasis and cardiovascular functions. Experimental data performed in rodents have shown that apelin has an aquaretic effect via its central and renal actions. In the brain, apelin inhibits the phasic electrical activity of vasopressinergic neurons and the release of vasopressin from the posterior pituitary into the bloodstream and in the kidney, apelin regulates renal microcirculation and counteracts in the collecting duct, the antidiuretic effect of vasopressin occurring via the vasopressin receptor type 2. In humans and rodents, if plasma osmolality is increased by hypertonic saline infusion/water deprivation or decreased by water loading, plasma vasopressin and apelin are conversely regulated to maintain body fluid homeostasis. In patients with the syndrome of inappropriate antidiuresis, in which vasopressin hypersecretion leads to hyponatremia, the balance between apelin and vasopressin is significantly altered. In order to re-establish the correct balance, a metabolically stable apelin-17 analog, LIT01-196, was developed, to overcome the problem of the very short half-life (in the minute range) of apelin in vivo. In a rat experimental model of vasopressin-induced hyponatremia, subcutaneously (s.c.) administered LIT01-196 blocks the antidiuretic effect of vasopressin and the vasopressin-induced increase in urinary osmolality, and induces a progressive improvement in hyponatremia, suggesting that apelin receptor activation constitutes an original approach for hyponatremia treatment.

The contribution of plasma urea to total osmolality during iatrogenic fluid reduction in critically ill patients

Hyperosmolality is common in critically ill patients during body fluid volume reduction. It is unknown whether this is only a result of decreased total body water, or an active osmole-producing mechanism similar to that in aestivating animals where muscle degradation increases urea levels to preserve water. We hypothesized that fluid volume reduction in critically ill patients contributes to a shift from ionic to organic osmolytes similar to mechanisms of aestivation. We performed a post-hoc analysis on data from a multicenter observational study in adult ICU patients in the post-resuscitative phase. Fluid, electrolyte, energy and nitrogen intake, fluid loss, estimated glomerular filtration rate (eGFR) and estimated plasma osmolality (eOSM) were registered. Contributions of osmolytes Na+, K+, urea and glucose to eOSM expressed as proportions of eOSM were calculated. 241 patients were included. eOSM increased (median change 7.4 mOsm/kg (IQR −1.9–18) during the study. The of sodium's and potassium's proportions of eOSM decreased (P &lt; 0.05 and P &lt; 0.01 respectively), whereas the urea's proportion increased (P &lt; 0.001). Urea's proportion of eOSM was higher in patients with negative vs. positive fluid balance. The urea's proportion of eOSM increased with eOSM (r = 0.63; adjusted for eGFR r = 0.80), but not nitrogen intake. In patients without furosemide and/or renal replacement therapy (n = 17), urea's proportion of eOSM and eOSM correlated strongly (r = 0.92). Urea's proportion of eOsm was higher in patients not surviving to 90 days. In stabilized ICU patients the contribution of urea to plasma osmolality increased during body water volume reduction, statistically independently of nitrogen administration and eGFR. The shift from ionic osmolytes to urea during body fluid volume reduction is similar to that seen in aestivating animals. ClinicalTrials.org Identifier: NCT03972475

Estrogen to Progesterone Ratio and Fluid Regulatory Responses to Varying Degrees and Methods of Dehydration

The purpose of this study was to investigate the relationship between volume regulatory biomarkers and the estrogen to progesterone ratio (E:P) prior to and following varying methods and degrees of dehydration. Ten women (20 ± 1 year, 56.98 ± 7.25 kg, 164 ± 6 cm, 39.59 ± 2.96 mL•kg•min−1) completed four intermittent exercise trials (1.5 h, 33.8 ± 1.3°C, 49.5 ± 4.3% relative humidity). Testing took place in two hydration conditions, dehydrated via 24-h fluid restriction (Dehy, USG &gt; 1.020) and euhydrated (Euhy, USG ≤ 1.020), and in two phases of the menstrual cycle, the late follicular phase (days 10–13) and midluteal phase (days 18–22). Change in body mass (%BMΔ), serum copeptin concentration, and plasma osmolality (Posm) were assessed before and after both dehydration stimuli (24-h fluid restriction and exercise heat stress). Serum estrogen and progesterone were analyzed pre-exercise only. Estrogen concentration did not differ between phases or hydration conditions. Progesterone was significantly elevated in luteal compared to follicular in both hydration conditions (Dehy—follicular: 1.156 ± 0.31, luteal: 5.190 ± 1.56 ng•mL−1, P &lt; 0.05; Euhy—follicular: 0.915 ± 0.18, luteal: 4.498 ± 1.38 ng·mL−1, P &lt; 0.05). As expected, E:P was significantly greater in the follicular phase compared to luteal in both hydration conditions (Dehy—F:138.94 ± 89.59, L: 64.22 ± 84.55, P &lt; 0.01; Euhy—F:158.13 ± 70.15, L: 50.98 ± 39.69, P &lt; 0.01, [all •103]). Copeptin concentration was increased following 24-h fluid restriction and exercise heat stress (mean change: 18 ± 9.4, P &lt; 0.01). We observed a possible relationship of lower E:P and higher copeptin concentration following 24-h fluid restriction (r = −0.35, P = 0.054). While these results did not reach the level of statistical significance, these data suggest that the differing E:P ratio may alter fluid volume regulation during low levels of dehydration but have no apparent impact after dehydrating exercise in the heat.

Copeptin and Stress

Vasopressin (AVP) and copeptin are released in equimolar amounts from the same precursor. Due to its molecular stability and countless advantages as compared with AVP, copeptin perfectly mirrors AVP presence and has progressively emerged as a reliable marker of vasopressinergic activation in response to osmotic and hemodynamic stimuli in clinical practice. Moreover, evidence highlighting the prognostic potential of copeptin in several acute diseases, where the activation of the AVP system is primarily linked to stress, as well as in psychologically stressful conditions, has progressively emerged. Furthermore, organic stressors induce a rise in copeptin levels which, although non-specific, is unrelated to plasma osmolality but proportional to their magnitude: suggesting disease severity, copeptin proved to be a reliable prognostic biomarker in acute conditions, such as sepsis, early post-surgical period, cardiovascular, cerebrovascular or pulmonary diseases, and even in critical settings. Evidence on this topic will be briefly discussed in this article.

Tolerance and osmotic response to food deprivation and salt loading in the herbivorous non-drinking Moroccan Spiny-tailed lizard Uromastyx nigriventris (Sauria: Agamidae)

Animals inhabiting arid environments use a variety of behavioural and physiological strategies to balance their water and salt budgets. We studied the effects of dehydration and salt loading on osmoregulatory capacities in a large herbivorous desert lizard, the Moroccan Spiny-tailed lizard Uromastyx nigriventris, the family Agamidae. These lizards select plants with a high K+ to Na+ ratio of 15 to 20, and like other herbivorous lizards, effectively eliminate the extra electrolyte load, mainly via a pair of active nasal salt glands, which exude the extra ions from blood. Here we present results of a series of laboratory experiments, which tested a five-week food and water deprivation and the excretory response of nasal salt glands, during a short period of five days, following salt loading by two separated injections of KCl or NaCl at a 5-day interval (4th and 9th days). During food-water deprivation, hypohydrated lizards lost 32% of their initial body mass with a substantial decrease of their Body Condition Index and the tail volume as an index of energy (fat and then potential metabolic water) storage. Plasma osmolality significantly increased by 20%. There were also significantly increased plasma sodium, chloride, and total protein concentrations. On the other hand, there was no significant decrease in the plasma glucose level. Most of the salt loaded lizards secreted far more K+ than Na+ via the nasal glands, even after NaCl loading. The K+/Na+ ratio decreased only after two to three repetitive NaCl injections but insufficient Na+ was eliminated. Two successive KCl injections were successfully eliminated, but daily natural average K+ administration induced progressive hyperkaliemia. These experimental data agreed with previous observations showing variations of plasma Na+ and K+ concentrations in free-living lizards. The nasal gland constitutes the main route of Cl− excretion but the Cl−/(Na+ + K+) ratio may vary according to observations in other herbivorous species.