Probiotics and Isoflavones as a Promising Therapeutic for Calcium Status and Bone Health: A Narrative Review

Probiotics have potential clinical effects for treating and preventing osteoporosis. Meanwhile, isoflavones have attracted much attention due to their ability to prevent postmenopausal symptoms. Research has established that probiotics and isoflavones can regulate hormones, immune cells, and the gastrointestinal system, acting as links in the gut–bone axis. However, combining the effects of probiotics and isoflavones on calcium status and bone health is a more novel and a still-evolving research area. Lactobacillus and Bifidobacterium are the foremost strains that influence bone health to a significant extent. Among the isoflavones, daidzein, genistein, and the metabolites of genistein (such as equol) stimulate bone formation. It can be concluded that probiotics and isoflavones promote bone health by regulating calcium uptake, gut microbiota, and various metabolic pathways that are associated with osteoblast activity and bone formation. Nevertheless, further experiments of probiotics and isoflavones are still necessary to confirm the association between calcium bioavailability and bone health.

Parathyroid Hormone Related Peptide Elevations in Normocalcemic Adults

Introduction/Objective Elevated parathyroid hormone-related peptide (PTHrP) is a biomarker often associated with hypercalcemia of malignancy. However, elevations of PTHrP can be seen in non-malignant patients with normal calcium status, notably renal failure. We investigate whether a LC-MS/MS test that specifically measures a peptide in the middle region of PTHrP fragments is immune to false elevations of PTHrP. Furthermore, we examine if PTHrP/PTH ratio or renal status can be used to further characterize PTHrP elevations in a cohort of normocalcemic patients. Methods/Case Report We conducted a retrospective study on adult patients that had at least one PTHrP laboratory test (i.e., ARUP PTHrP by LC-MS/MS) within the past 10 years (01/01/2011 to 04/29/2021) at a large academic center. We further stratified this cohort by demographics and additional laboratory markers including calcium status, parathyroid hormone (PTH) (i.e., by Siemens Centaur assay (Malvern, PA)), renal status, and known malignancies. Results (if a Case Study enter NA) We identified a total of 941 patients (585 female and 356 male). 33% of patients (30% [70/233] female and 36% [84/236] male) with elevated PTHrP were normocalcemic (i.e., did not have an elevation in calcium, ionized calcium, or diagnosis of hypercalcemia). 95% (21/22) of normocalcemic males and 100% (17/17) of normocalcemic females with an elevated PTHrP and elevated PTH had a PTHrP/PTH ratio below the normal sex specific reference ranges of 1.07 and 1.86, respectively. A subset of normocalcemic patients with elevated PTHrP had an estimated glomerular filtration rate (eGFR) recorded. Of these patients, 100% (58/58) of females and 94% (65/59) of males had an eGFR below 90 mL/min/1.73 m2 had an eGFR less than 30 mL/min/1.73 m2. and 50% (29/58) of females and 38% (26/69) of males Conclusion Our study supports the hypothesis that elevated PTHrP in the setting of normal calcium may occur due to renal insufficiency.

Comparative Analysis of Whole Blood Ionised Calcium, Lactate and Chloride Concentrations by Gem Premier 3000 and Edan I15 Vet and the Effect of Parity and Postpartum Blood Collection Time on Blood Calcium Status in Holstein With and Without Subclinical Hypocalcemia - Part 1

Lactating Holstein (n=125) were enrolled randomly for the coccygeal whole blood analysis by blood gas devices GEM Premier 3000 (GEM) and Edan i15 Vet (EDAN) between calving to postpartum day 3 (G1) and postpartum day 4 to 27 (G2). Blood pH, ionised calcium (ICA7.4) and lactate analysis were significantly correlated between GEM and EDAN (r=0.86, 0.94, 0.87 respectively). The bias for ICA7.4, lactate and pH analysis was -0.054, -0.344 mmol/L and +0.009 respectively. ICA7.4 was correlated negatively with parity and chloride, but positively with lactate. The averages of ICA7.4 and serum total calcium (TC) was significantly lower in G1 than G2. Chloride and lactate were significantly higher in G1 than G2. Subclinical hypocalcemia prevalence (SCH) (serum TC<2.15 mmol/L, as reference) was 52.9% in G1 and 21.1% in G2. Cows with SCH had frequently over 50% ICA7.4/TC ratio. Sensitivity analysis provided a sensitivity of 57.4% for ICA7.4 cut-points of 1.02 (GEM) and 1.05 (EDAN) mmol/L to detect SCH based on reference serum TC. Primiparous (PRP) with and without SCH in G1 had significantly higher ICA7.4 than multiparous (MUL). Cows with SCH had significantly higher chloride in G1 than G2. MUL had significantly higher lactate and chloride in G1 than G2. Conclusively, ICA7.4 and pH analysis between GEM and EDAN were correlated well with acceptable biases, but high differences occurred in lactate analysis. MUL was at risk in G1 due to lower ICA7.4 and TC over PRP. Higher ICA7.4 of PRP can reduce the risk and frequency of clinical hypocalcemia. SCH correlated negatively with Cl concentration in G1, but not lactate.

Pepper Stip: An Abiotic Disorder of Unknown Cause Affecting Pepper Fruit

Pepper stip (meaning speck in German), also referred to as color speck or colour spotting outside the US, is considered a physiological disorder of pepper. The disorder is believed to be related to high calcium status with levels of NH3-N and K playing a role. This 3-page factsheet of the UF/IFAS Plant Pathology Department summarizes known symptoms, causes, and potential environmental stressors that may result in stip development on peppers. Written by Camille McAvoy and Pamela Roberts.

Polymorphisms Contributing to Calcium Status: A Systematic Review

This systematic review assessed genotypes and changes in calcium homeostasis. A literature search was performed in EMBASE, Medline and CENTRAL on 7 August 2020 identifying 1012 references. Studies were included with any human population related to the topic of interest, and genetic variations in genes related to calcium metabolism were considered. Two reviewers independently screened references, extracted relevant data and assessed study quality using the Q-Genie tool. Forty-one studies investigating Single Nucleotide Polymorphisms (SNPs) in relation to calcium status were identified. Almost half of the included studies were of good study quality according to the Q-Genie tool. Seventeen studies were cross-sectional, 14 case-control, seven association and three were Mendelian randomization studies. Included studies were conducted in over 18 countries. Participants were mainly adults, while six studies included children and adolescents. Ethnicity was described in 31 studies and half of these included Caucasian participants. Twenty-six independent studies examined the association between calcium and polymorphism in the calcium-sensing receptor (CASR) gene. Five studies assessed the association between polymorphisms of the Vitamin D receptor (VDR) gene and changes in calcium levels or renal excretion. The remaining ten studies investigated calcium homeostasis and other gene polymorphisms such as the CYP24A1 SNP or CLDN14. This study identified several CASR, VDR and other gene SNPs associated with calcium status. However, to provide evidence to guide dietary recommendations, further research is needed to explore the association between common polymorphisms and calcium requirements.