Cognitive impairment reversed by cinacalcet administration in primary hyperparathyroidism

Sweet, bloody consumption - what we eat and how it affects vascular ageing, the BBB and kidney health in CKD

In today's industrialized society food consumption has changed immensely toward heightened red meat intake and use of artificial sweeteners instead of grains and vegetables or sugar, respectively. These dietary changes affect public health in general through an increased incidence of metabolic diseases like diabetes and obesity, with a further elevated risk for cardiorenal complications. Research shows that high red meat intake and artificial sweeteners ingestion can alter the microbial composition and further intestinal wall barrier permeability allowing increased transmission of uremic toxins like p-cresyl sulfate, indoxyl sulfate, trimethylamine n-oxide and phenylacetylglutamine into the blood stream causing an array of pathophysiological effects especially as a strain on the kidneys, since they are responsible for clearing out the toxins. In this review, we address how the burden of the Western diet affects the gut microbiome in altering the microbial composition and increasing the gut permeability for uremic toxins and the detrimental effects thereof on early vascular aging, the kidney per se and the blood-brain barrier, in addition to the potential implications for dietary changes/interventions to preserve the health issues related to chronic diseases in future.

Primary Hyperparathyroidism in Older Adults: A Narrative Review of the Most Recent Literature on Epidemiology, Diagnosis and Management

BACKGROUND

Primary hyperparathyroidism (PHPT) is a common endocrine disorder among older adults. The aim of this review is to shed light on PHPT, particularly in this age group, in terms of prevalence, clinical manifestations, medical and surgical management, and post-operative complications.

METHODS

Eligible studies were those considering PHPT exclusively in the older population (main databases: PubMed, Medline, Google Scholar and the University Online database). Articles published in the last 10 years (2013-2023) were considered. Eligibility criteria followed the SPIDER (sample, phenomenon of interest, design, evaluation, research type) tool. The methodological quality of the studies was assessed using the Joanna Briggs Institute critical appraisal tool. A total of 29 studies (mainly observational) matched the inclusion criteria.

RESULTS

The prevalence of PHPT is approximately 1 per 100 in the elderly, and it is more common in females. The clinical presentation varies by age and can include osteoporosis, fractures, and neuropsychiatric symptoms. Conservative management can be an option whenever surgery is not indicated or feasible. However, parathyroidectomy (PTX) remains a safe and effective modality in aging populations with improvement to symptoms, bone mineral density, fracture risk, frailty, quality of life, and metabolic derangements. Complication rates are similar in elderly people compared to younger ones, except for mildly longer length of hospital stay and reoperation for those with higher frailty.

CONCLUSION

PHPT is a common yet overlooked and underdiagnosed condition among the older population. The safety and efficacy of PTX in the older population on different levels is now well demonstrated in the literature.

Quality of Life in Primary Hyperparathyroidism

Quality of life is impaired in primary hyperparathyroidism (PHPT), regardless of the severity of the disease. Clinical studies have employed different instruments, including standardized and disease-specific questionnaires, and including patients with different phenotypes of PHPT. Neuropsychiatric symptoms and decline in cognitive status are common in PHPT. Patients may complain of these issues or they can be ascertained by questionnaires; they include depression, anxiety, impaired vitality, social and emotional functions, sleep disturbances, and altered mental function. Randomized controlled trials on the effects of surgical versus non-surgical treatments have collectively shown improvement in quality of life after parathyroidectomy, but results have been heterogeneous.

The dopamine system: insights between kidney and brain

BACKGROUND

Chronic kidney disease (CKD) is one of the most common diseases in adult age and it is typical of older adults. Recent data suggest that almost half of the elders have CKD. It is now clear that CKD is accompanied, in the early stages, by cognitive impairment, together with depression and subtle abnormalities in motor control (such as gait and balance alterations).

SUMMARY

Several data suggest a link between brain dopamine and kidney diseases. Metabolic syndrome and diabetes can affect dopamine neuron survival (leading to Parkinson's Disease). Several uremic toxins in CKD (uric acid, indoxyl sulphate) and trace elements accumulating in CKD (aluminium, manganese) can also modify the dopaminergic system. Hormones produced by the kidney such as vitamin D are neuroprotective for dopamine neurons. Dopaminergic drugs are useful for the treatment of a common sleep disorder in CKD, the restless legs syndrome. However, experiments on animal models of CKD show conflicting results regarding a modification of dopamine neurons.

KEY MESSAGES

Several observations suggest a limited relevance of the dopaminergic system in CKD-related cognitive impairment. However, a common sleep disturbance in CKD, the restless leg syndrome, improves with dopaminergic drugs. Therefore, it remains to be established the role of the dopamine system in subtle motor dysfunction observed in CKD, such as tremors, gait alterations, and central sleep apnea.

High-Phytate Diets Increase Amyloid β Deposition and Apoptotic Neuronal Cell Death in a Rat Model

Amyloid-β (Aβ) accumulation in the hippocampus is an essential event in the pathogenesis of Alzheimer's disease. Insoluble Aβ is formed through the sequential proteolytic hydrolysis of the Aβ precursor protein, which is cleaved by proteolytic secretases. However, the pathophysiological mechanisms of Aβ accumulation remain elusive. Here, we report that rats fed high-phytate diets showed Aβ accumulation and increased apoptotic neuronal cell death in the hippocampus through the activation of the amyloidogenic pathway in the hippocampus. Immunoblotting and immunohistochemical analyses confirmed that the overexpression of BACE1 β-secretase, a critical enzyme for Aβ generation, exacerbated the hippocampal Aβ accumulation in rats fed high-phytate diets. Moreover, we identified that parathyroid hormone, a physiological hormone responding to the phytate-mediated dysregulation of calcium and phosphate homeostasis, plays an essential role in the transcriptional activation of the Aβ precursor protein and BACE1 through the vitamin D receptor and retinoid X receptor axis. Thus, our findings suggest that phytate-mediated dysregulation of calcium and phosphate is a substantial risk factor for elevated Aβ accumulation and apoptotic neuronal cell death in rats.