Parathyroid hormone 2 receptor and its endogenous ligand tuberoinfundibular peptide of 39 residues are concentrated in endocrine, viscerosensory and auditory brain regions in macaque and human

Hypoparathyroidism update

PURPOSE OF REVIEW

Since the release of the 2022 Second International Workshop Evaluation and Management of Hypoparathyroidism Summary Statement and Guidelines, updates and advances are now available in the cause, complications, and treatment of adult chronic hypoparathyroidism (hypoPTH). This review aims to highlight these new findings and implications to patient care.

RECENT FINDINGS

Postsurgical hypoparathyroidism remains the most common cause, immune-related hypoparathyroidism from checkpoint inhibitors is an emerging autoimmune cause. In a large retrospective cohort study of thyroidectomies, incident fracture was lower, particularly in the vertebra, in the hypoPTH cohort, compared with postthyroidectomy control group. Hypercalciuria increases risk for renal calculi in hypoPTH independent of disease duration and treatment dose. Quality of life is impaired in hypoPTH patients on conventional therapy, improvement was noted post-PTH replacement. TranCon PTH phase 3 RCT reported eucalcemia with reduced renal calcium excretion, normalization of bone turn-over markers, stable BMD and improved quality of life.

SUMMARY

HypoPTH is a chronic disease associated with significant morbidity and poor Quality of Life. Awareness of treatment targets and follow-up investigations can alleviate patient anxiety regarding over-treatment and under-treatment. Progress in long-acting PTH replacement strategies might provide accessible, feasible alternatives to conventional therapy in brittle hypoPTH patients.

Preclinical development of EXT608, an investigational parathyroid hormone derivative with extended half-life for the treatment of hypoparathyroidism

Hypoparathyroidism, a deficiency of parathyroid hormone (PTH), results in hypocalcemia, hyperphosphatemia, and hypercalciuria. The disease is poorly controlled by calcium and vitamin D supplements or native PTH(1-84) replacement therapy. A version of PTH is being developed using D-VITylation technology, whereby vitamin D is conjugated to a therapeutic peptide, which confers a long plasma half-life by virtue of binding to the abundant vitamin D binding protein (DBP). D-VITylation of PTH caused no reduction in activity at the PTHR1 receptor, and resulted in a plasma elimination half-life of 7-15 h in rats and 24-32 h in cynomolgus monkeys. Analysis of steady-state pharmacokinetics as a function of dose showed flat profiles with smaller peak:trough ratios at low doses, indicative of slower subcutaneous absorption. In thyroparathyroidectomized (TPTx) rats, PTH(1-34)-vitamin D conjugates restored serum calcium and phosphate levels into the normal range over the 24 h dosing period, and increased bone turnover markers and reduced bone mineral density. Urinary calcium was initially elevated, but normalized by the end of treatment on day 27. In healthy monkeys, a single dose of PTH(1-34)-vitamin D conjugates elevated serum calcium levels above the normal range for a period of 24-48 h while simultaneously reducing urinary calcium. Therefore, the lead compound, EXT608, is a promising candidate as a therapeutic that can truly mimic the endogenous activity of PTH and warrants further study in patients with hypoparathyroidism.

Interactions between PTH and adiposity: appetizing possibilities

Although parathyroid hormone (PTH) is best known for its role as a regulator of skeletal remodelling and calcium homeostasis, more recent evidence supports a role for it in energy metabolism and other non-classical targets. In this report, we summarize evidence for an effect of PTH on adipocytes. This review is based upon all peer-reviewed papers, published in the English language with PubMed as the primary search engine. Recent preclinical studies have documented an effect of PTH to stimulate lipolysis in both adipocytes and liver cells and to cause browning of adipocytes. PTH also reduces bone marrow adiposity and hepatic steatosis. Although clinical studies are limited, disease models of PTH excess and PTH deficiency lend support to these preclinical findings. This review supports the concept of PTH as a polyfunctional hormone that influences energy metabolism as well as bone metabolism.

Evaluation of the Quality of Life in Moroccan Patients Diagnosed with Hypoparathyroidism

Objective

Hypoparathyroidism (HPt) is a rare endocrine disorder often of postsurgical origin, resulting in hypocalcaemia. Several complications have been described including impairment of quality of life (QoL). Our study aims to evaluate the effect of hypoparathyroidism on the QoL of patients diagnosed with HPt.

Methods

A cross-sectional study was conducted in the Department of Endocrinology, Diabetology, Metabolic Diseases and Nutrition of the Hassan II University Hospital of Fez. We included in our study all patients followed for chronic HPt. Well-being was assessed using the WHO 5 index, and QoL was assessed by the SF-36 questionnaire in its validated Arabic version. Data were entered into Excel and analysed using SPSS 26. Multiple linear regression was utilized to ascertain the variables linked to the QoL in individuals diagnosed with HPt.

Results

A total of 143 patients with HPt were included in the study, 86.7% of whom were female. The mean age of the patients was 44.6 ± 17.3 years. 89.9% were of postsurgical etiology. The assessment of well-being by the WHO 5 index showed a low score (<50), meaning poor well-being in 44.8%. Regarding the QoL, the assessment showed low scores in the areas of general health (41.7), limitations due to physical condition (40.5), vitality (41.4), and limitations due to psychological condition (42.6). The multiple linear regression model revealed a noteworthy association between low SF-36 score and advanced age (β = -5.91; p < 0.001), surgical etiology (β = 8.71; p < 0.001), low education level (β = -10.1; p < 0.001), and poor compliance with medication (β = -11.3; p < 0.001). However, the relationship between impaired QoL and achievement of normocalcemia was nonsignificant (p=0.69).

Conclusions

Our work objective is that patients with HPt have a reduced and multifactorial QoL. Despite normocalcemia, it is hypothesized that parathyroid hormone directly influences QoL. These results could serve as a basis for future research.

Quality of life in patients with hypoparathyroidism receiving standard treatment: an updated systematic review

PURPOSE

Hypoparathyroidism is defined by hypocalcemia with inappropriately normal or low parathyroid hormone levels. The current standard treatment consists of lifelong calcium and/ or vitamin D supplementation. Even while on stable treatment regimens, hypoparathyroid patients might still suffer from symptoms that can negatively impact their quality of life.

METHODS

A systematic literature review to identify the current knowledge regarding quality of life in patients with hypoparathyroidism receiving standard treatment was performed on November 1st, 2023. PubMed as well as Web of Science were searched. The systematic review is registered in PROSPERO (#CRD42023470924).

RESULTS

After removal of duplicates, 398 studies remained for title and abstract screening, after which 30 were included for full-text screening. After exclusion of seven studies with five studies lacking a control population, one using a non-validated questionnaire, and one being a subsample of the larger included study, 23 studies were included in this systematic review. The majority of the included studies used a guideline-conform definition of hypoparathyroidism, and the SF-36 was the most often applied tool. Almost all studies (87%) reported statistically significantly lower scores in at least one quality of life domain compared to a norm population or controls.

CONCLUSION

Patients with hypoparathyroidism receiving standard treatment report impairments in quality of life. The reasons for these impairments are probably multifaceted, making regular monitoring and the inclusion of various professionals necessary.

PTH level might be associated with impaired quality of life in patients with nonsurgical hypoparathyroidism

OBJECTIVE

Nonsurgical hypoparathyroidism (ns-HP) is a rare disease. There are few studies on Quality of Life (QoL) among patients with ns-HP. This study aimed to investigate the QoL among ns-HP patients with regular conventional treatment, and explore the influence factors affecting QoL among these Chinese ns-HP patients.

METHODS

This is a cross-sectional study comparing 101 patients identified as ns-HP and 101 healthy controls. The questionnaires of Short Form 36 Health Survey questionnaire version 2(SF-36v2) were used to evaluate QoL.

RESULTS

Scores of all eight subdomains of SF-36v2 and physical component scores (PCS), mental component scores (MCS) were significantly lower in the ns-HP group compared with the healthy controls. The indices of all subdomains of SF-36v2 between Q1 (the lowest quartile) and Q4 (the highest quartile) groups were compared, suggesting higher percentages of detectable parathyroid hormone (PTH) before treatment in Q4 group among all QoL indices except two subdomains (physical function and body pain).

CONCLUSION

Both mental and physical QoL were impaired in the ns-HP patients even with regular conventional treatment for hypocalcemia, which were more severe in cases with lower baseline PTH levels.

Assessment of quality of life in patients with permanent hypoparathyroidism receiving conventional treatment

Introduction

Patients with permanent hypoparathyroidism suffer from multiple complaints and are exposed to long-term complications that might compromise their well-being. The aim of this study was to assess the quality of life (QoL) in patients with permanent hypoparathyroidism receiving conventional therapy and to determine the associated factors.

Methods

This was a cross-sectional matched case-control study including 53 patients with permanent hypoparathyroidism and 53 matched controls. Biochemical blood parameters (calcium, phosphate, albumin, magnesium, 25-hydroxy-vitamin D, creatinine, TSH, and PTH) and 24-hours calciuria were measured in patients with hypoparathyroidism. QoL was assessed in all participants using the Short Form 36 Health Survey (SF-36).

Results

The study included 53 patients (41 women and 12 men) with hypoparathyroidism receiving conventional therapy.Their mean age was 52.8 ± 16.5 years. In comparison with controls, patients with hypoparathyroidism had significantly lower scores in all eight domains of SF-36 (p < 10- 3). Patients with poor socioeconomic conditions had lower SF-36 scores than those with good conditions.The etiology of hypoparathyroidism, the disease duration, the control of the disease, and the body mass index did not significantly interfere with SF-36 scores. SF-36 total score was negatively correlated with age (r=-0.619, p < 10- 3) and symptoms of hypocalcemia (r=-0.284, p = 0.039), and positively correlated with creatinine clearance (r = 0.559, p < 10- 3), magnesium level (r = 0.345, p = 0.011), and 25 hydroxy-vitamin D level (r = 320, p = 0.021). No significant correlations were found between SF-36 scores and other biological parameters such as calcemia, phosphatemia, phosphocalcic product, PTH, TSH, and calciuria.

Conclusion

Patients with permanent hypoparathyroidism had impairment in their QoL. Age, socioeconomic conditions, renal function, magnesium level, and 25 hydroxy-vitamin D level may interfere in the decline of the QoL of these patients.

Impairments in quality of life and predictors of symptom burden in patients with hypoparathyroidism: results from a population-based survey

PURPOSE

To investigate the quality of life (QoL) in patients with hypoparathyroidism (hypoPT) compared to the general population and to identify sociodemographic and clinical factors that are associated with symptom burden.

METHODS

Patients with a diagnosis of hypoPT participated in an online survey. Information regarding the survey was distributed by treating physicians or a self-help organization. Quality of life was assessed using the EORTC QLQ-C30 and symptom burden using the Hypoparathyroid Patient Questionnaire (HPQ28). Multivariate linear regression analysis was used to compare QoL of hypoPT patients with the general population (adjusted for age, sex, education)and to identify factors associated with symptom burden.

RESULTS

Altogether, 264 hypoPT patients provided information on QoL and symptom burden. HypoPT was associated with worse cognitive (β = -15.9; p < 0.01) and emotional functioning (β = -12.3; p = 0.04) compared to the general population. The highest symptom burden in hypoPT patients was observed for the domains loss of vitality (mean: 61.4; SD: 21.9), pain and cramps (mean: 43.7; SD: 26.5), and numbness and tingling sensations (mean: 38.9; SD: 30.0). Female gender was associated with a higher symptom burden across all nine domains of the HPQ28, while longer disease duration was associated with a lower symptom burden in neurovegetative symptoms, loss of vitality, depression and anxiety, and depressive symptoms.

CONCLUSION

HypoPT patients have impaired QoL compared to the general population. Being female is strongly associated with high symptom burden.

Conserved islands of divergence associated with adaptive variation in sockeye salmon are maintained by multiple mechanisms

Local adaptation is facilitated by loci clustered in relatively few regions of the genome, termed genomic islands of divergence. The mechanisms that create and maintain these islands and how they contribute to adaptive divergence is an active research topic. Here, we use sockeye salmon as a model to investigate both the mechanisms responsible for creating islands of divergence and the patterns of differentiation at these islands. Previous research suggested that multiple islands contributed to adaptive radiation of sockeye salmon. However, the low-density genomic methods used by these studies made it difficult to fully elucidate the mechanisms responsible for islands and connect genotypes to adaptive variation. We used whole genome resequencing to genotype millions of loci to investigate patterns of genetic variation at islands and the mechanisms that potentially created them. We discovered 64 islands, including 16 clustered in four genomic regions shared between two isolated populations. Characterisation of these four regions suggested that three were likely created by structural variation, while one was created by processes not involving structural variation. All four regions were small (< 600 kb), suggesting low recombination regions do not have to span megabases to be important for adaptive divergence. Differentiation at islands was not consistently associated with established population attributes. In sum, the landscape of adaptive divergence and the mechanisms that create it are complex; this complexity likely helps to facilitate fine-scale local adaptation unique to each population.

The Influence of Hyperparathyroidism Patient Profile on Quality of Life After Parathyroidectomy

BACKGROUND

Improvements in quality of life (QoL) after parathyroidectomy in patients with primary hyperparathyroidism (PHPT) is discussed. It has not been analyzed whether these improvements can be influenced by a specific socio-personal or clinical patient profile.

OBJECTIVES

to analyze QoL differences after parathyroidectomy and to determine a socio-personal and clinical profile that influences improvement after parathyroidectomy.

METHODS

A longitudinal prospective cohort study in patients with PHPT. SF-36 and PHPQOL questionnaires were completed by the patients. A comparative preoperatory analysis was carried out, at three and twelve months after surgery. Student's t test was used for the correlations. The size of the effect was assessed using G*Power software. A multivariate analysis was performed to evaluate the socio-personal and clinical variables affecting the improvement in QoL after surgery.

RESULTS

Forty-eight patients were analyzed. Three months after surgery an improvement was found in physical function, general health, vitality, social function, emotional role, mental health and in the patient's declared health assessment. One year after the intervention a general improvement was observed, with a greater effect on mental health and declared health evolution. Patients with bone pain presented with a higher probability of improvement after surgery. Patients with prior psychological disease had a lower associated probability of an improvement and high levels of PTH related to a greater probability of improvement after surgery.

CONCLUSIONS

There is an improvement in the QoL of PHPT patients after parathyroidectomy. Patients with bone pain and high PTH levels prior to the parathyroidectomy present with a greater probability of having a greater improvement in QoL after surgery.

Parathyroid Hormone (PTH)-Related Peptides Family: An Intriguing Role in the Central Nervous System

Parathyroid Hormone (PTH) plays a crucial role in the maintenance of calcium homeostasis directly acting on bone and kidneys and indirectly on the intestine. However, a large family of PTH-related peptides exists that exerts other physiological effects on different tissues and organs, such as the Central Nervous System (CNS). In humans, PTH-related peptides are Parathyroid Hormone (PTH), PTH-like hormones (PTHrP and PTHLH), and tuberoinfundibular peptide of 39 (TIP39 or PTH2). With different affinities, these ligands can bind parathyroid receptor type 1 (PTH1R) and type 2 (PTH2R), which are part of the type II G-protein-coupled-receptors (GPCRs) family. The PTH/PTHrP/PTH1R system has been found to be expressed in many areas of the brain (hippocampus, amygdala, hypothalamus, caudate nucleus, corpus callosum, subthalamic nucleus, thalamus, substantia nigra, cerebellum), and literature data suggest the system exercises a protective action against neuroinflammation and neurodegeneration, with positive effects on memory and hyperalgesia. TIP39 is a small peptide belonging to the PTH-related family with a high affinity for PTH2R in the CNS. The TIP39/PTH2R system has been proposed to mediate many regulatory and functional roles in the brain and to modulate auditory, nociceptive, and sexual maturation functions. This review aims to summarize the knowledge of PTH-related peptides distribution and functions in the CNS and to highlight the gaps that still need to be filled.

Serum calcium levels are associated with cognitive function in hypoparathyroidism: a neuropsychological and biochemical study in an Italian cohort of patients with chronic post-surgical hypoparathyroidism

PURPOSE

Hypoparathyroidism (HypoPT) is a rare endocrine disease and conventional therapy is based on calcium and vitamin D analogues. Conventional therapy does not restore calcium homeostasis and patients complain with neuropsychological symptoms, which have been evaluated with nonspecific self-administered questionnaires. This study aims to evaluate cognitive functions of patients with chronic post-surgical (PS)-HypoPT compared to a control population, using a standardized neuropsychological approach and evaluating the relationship with serum calcium (Alb-Ca).

METHODS

Observational, monocentric study on 33 patients with PS-HypoPT and 24 controls, in whom biochemical testing and a standardized neuropsychological assessment by a trained psychologist were performed.

RESULTS

In patients with PS-HypoPT, low Alb-Ca correlated with a worse performance on semantic memory abilities and executive function, as suggested by a significant inverse correlation between Alb-Ca and Trail Making Test A (TMT-A) scores (r = - 0.423; p = 0.014) and by a positive correlation with Semantic Fluency Test scores (SF)(r = 0.510; p = 0.002). PS-HypoPT patients with Alb-Ca ≤ 8.9 mg/dl had a significantly lower test performance compared with PS-HypoPT patients with Alb-Ca > 8.9 mg/dl, both at the TMT-A test (mean score: 34.53-18.55; p < 0.0001) and at SF test (mean score: 41.94-48.68; p = 0.01) and also a significantly lower test performance compared with control patients' group at TMT-A (mean score: 34.53-25.5; p = 0.0057).

CONCLUSIONS

Patients with chronic PS-HypoPT in conventional therapy do not show a severe cognitive impairment; however, cognitive functions namely visuo-spatial attention, executive function and semantic memory appear to be modulated by Alb-Ca and impaired by its low levels.

Behavioural actions of tuberoinfundibular peptide 39 (parathyroid hormone 2)

Tuberoinfundibular peptide of 39 residues (TIP39) acts via its endogenous class B G-protein coupled receptorthe parathyroid hormone 2 receptor (PTH2R). Hence, it is also known as parathyroid hormone 2. The peptide is expressed in the brain by a small number of neurons with a highly restricted distribution, which in turn project to a large number of brain regions that contain PTH2R. This peptide neuromodulator system has been extensively investigated over the past 20 years including its behavioural actions, such as its role in the control of nociception, fear and fear incubation, anxiety and depression-like behaviours, and maternal and social behaviours. It also influences thermoregulation and potentially auditory responses. TIP39 probably exerts direct effect on the neuronal networks controlling these behaviours based on the localization of PTH2R and local TIP39 actions. In addition, TIP39 also affects the secretion of several hypothalamic hormones providing the basis for indirect behavioural actions. Recently developed experimental tools have stimulated further behavioural investigations, and novel results obtained are discussed in this review.

What are predictors of impaired quality of life in patients with hypoparathyroidism?

CONTEXT

Hypoparathyroidism (hypoPT) is a rare endocrine disorder. Little is known about what factors are associated with potential quality of life (QOL) impairments.

DESIGN

HypoPT patients at a minimum of 6 months' post diagnosis were invited to participate in an online survey through their treating physician or through self-help organisations METHODS: Impairments of clinical importance in QOL were considered present if the score of the respective functioning scale of the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 exceeded a pre-defined threshold. Symptom burden was assessed using the HPQ-28. Multivariate logistic regression was used to identify factors associated with impairments in QOL.

RESULTS

Data were available for 264 hypoPT patients. Impairments of clinical importance in QOL were reported for 40.4% in role functioning (RF), 40.6% in social functioning (SF), 60.8% in physical functioning (PF), 65.5% in cognitive functioning (CF) and 76.0% in emotional functioning (EF). Higher odds for reporting impaired QOL were seen for higher symptom burden (for almost all domains) and for being unable to work (for PF, RF and SF). Surgery for thyroid cancer being the cause of hypoPT was associated with lower odds in PF for patients and in PF and CF for patients with surgery for other thyroid-related diseases being the hypoPT cause.

CONCLUSIONS

HypoPT needs to be recognised as a disease which might be associated with impaired QOL and affect daily living. Symptom management is crucial for improving QOL in hypoPT patients but socioeconomic factors like work-ability need to be considered when treating hypoPT patients.

Renal complications and quality of life in postsurgical hypoparathyroidism: a case-control study

PURPOSE

Conventional therapy (calcium and activated vitamin D) does not restore calcium homeostasis in patients with chronic hypoparathyroidism (HypoPT) and is associated with renal complications and reduced quality of life (QoL). The aim of this study was to evaluate in a case-control, cross-sectional study, the rate of renal complications and QoL in two sex- and age-matched cohort of patients with differentiated thyroid cancer with (n = 89) and without (n = 89) chronic post-operative HypoPT (PoHypoPT) and their relationship with the biochemical control of the disease.

METHODS

Serum and urinary parameters, renal ultrasound and QoL were assessed by SF-36 and WHO-5 questionnaires.

RESULTS

Forty-three (48.3%) PoHypoPT patients reported symptoms of hypocalcemia. Twenty-six (29.2%) patients were at target for all 6 parameters, 46 (51.6%) for 5. The most frequently unmet targets were gender-specific 24-h urinary calcium (44.9%) and serum calcium (37.1%). Serum phosphate, magnesium and 25(OH)D were in the normal range in > 90% of patients. Renal calcifications were found in 26 (29.2%) patients, with no correlation with 24-h urinary calcium. eGFR did not differ between patients and controls. Conversely, patients had a significant higher rate of renal calcifications and a lower SF-36, but not WHO-5, scores. SF-36 scores did not differ between PoHypoPT patients who were, or not, hypocalcemic.

CONCLUSIONS

Our study shows that the rate of renal calcifications was higher in patients with PoHypoPT than in those without. This finding, together with the reduced QoL and the presence of hypocalcemic symptoms in about half patients, underscores that the treatment of chronic HypoPT with conventional therapy is suboptimal.

Impact of Permanent Post-thyroidectomy Hypoparathyroidism on Self-evaluation of Quality of Life and Voice: Results from the National QoL-hypopara Study

OBJECTIVE

To compare the quality of life (mental health) and voice in patients with or without permanent hypoparathyroidism after total thyroidectomy.

SUMMARY BACKGROUND DATA

Permanent hypoparathyroidism is an underestimated complication of thyroid surgery owing to suppression of parathormone secretion. Few studies have evaluated the consequences of hypoparathyroidism on quality of life and none has studied its effects on voice.

METHODS

The QoL-hypopara study (ClinicalTrial.gov NCT04053647) was a national observational study. Adult thyroidectomized patients were included between January and June 2020. A Serum parathormone level <15pg/mL more than 6 months after surgery defined permanent hypoparathyroidism. Patients answered the MOS-36-item short-form health (SF-36), the Voice Handicap Index (VHI) surveys, and a list of questions regarding their symptoms.

RESULTS

141 patients were included, 45 with permanent hypoparathyroidism. The median period between thyroid surgery and the questionnaire was 6 [Q1-Q3 4-11] and 4 [4-5] years in hypoparathyroid patients and controls respectively. Hypoparathyroid patients presented a reduced median mental score ratio (SF-36) (0.88 [Q1-Q3 0.63-1.01] versus 1.04 [0.82-1.13], P=0.003) and a lower voice quality (incidence rate ratio for total VHI 1.83-fold higher, P<0.001). In multivariable analysis, hypoparathyroidism (-0.17 [95%CI -0.28--0.07], P=0.002), but not age, female sex, thyroid cancer, or abnormal TSH level, was associated with the reduced mental score ratio. Myalgia, joint pain, paresthesia, tetany, anxiety attack and exhaustion were the most common symptoms among hypoparathyroid patients (>50%).

CONCLUSIONS

Hypoparathyroid patients present significantly impaired quality of life, lower voice quality and frequent symptoms. These results reinforce the importance of preventing this complication.

The association between hypoparathyroidism and cognitive impairment: a systematic review

CONTEXT AND PURPOSE

Hypocalcemia and low parathyroid hormone levels have been commonly suggested as factors able to induce central nervous system disturbances. However, evidences on the occurrence of cognitive impairment are limited or underestimated. The aim of this review is, therefore, to systematically summarize the available evidence concerning the occurrence of cognitive impairment among subjects suffering from idiopathic or secondary hypoparathyroidism.

METHODS

A systematic selection of the available literature was performed by searching the online databases PubMed, Scopus and Web of Knowledge.

RESULTS

The present systematic review included sixteen case report articles and one cross-sectional controlled study. Case reports were the most representative literature sources and involved ten women and seven men. The presence of cognitive impairment was mostly discussed in association with idiopathic hypoparathyroidism (HPT); five articles described the occurrence of cognitive impairment following postsurgical HPT. The case-controlled study reported a significant presence of peculiar cognitive deficits (e.g. reduced inhibitory control, impairment in visuo-spatial functioning among, and psychomotor retardation) among HPT subjects compared to healthy controls, with serum total calcium and its product with phosphorus as independent predictors of neuropsychological dysfunctions.

CONCLUSION

Even though mostly based on single case reports, the presence of neuropsychological dysfunctions in the context of HPT appears to be a consistent core finding.

Quality of Life in Patients With Asymptomatic Primary Hyperparathyroidism After Parathyroidectomy: A 3-Year Longitudinal Study

OBJECTIVE

Impaired quality of life (QoL) is considered as a nonclassical manifestation of primary hyperparathyroidism (PHPT). This study aimed to detect and compare changes in the QoL of patients with asymptomatic PHPT who had successful curative parathyroidectomy (PTX) 3 months and 3 years after the procedure.

METHODS

Patients with diagnosed PHPT were eligible for the study. There were 2 groups: the PTX group, with patients who underwent PTX, and the non-PTX group, with patients who were treated conservatively. QoL was assessed using Pasieka's Parathyroid Assessment of Symptoms Questionnaire (PAS-Q) at baseline, 3 months, and 3 years.

RESULTS

Thirty-eight patients were included in the study: 18 in the PTX group and 20 in the non-PTX group. In the PTX group, the mean PAS-Q total score before PTX was 518, which was reduced significantly at the 3-month (P = .003) and 3-year assessments (P = .001). However, in the non-PTX group, the mean PAS-Q total score was 326 at baseline and increased continuously for 3 years (P = .019). At the 3-year evaluation, the mean total score was significantly higher compared to that of the PTX group (P = .021). Finally, there was a positive correlation between total serum calcium and PAS-Q score in the non-PTX group (r = 0.524, P = .018).

CONCLUSION

QoL of patients with PHPT improved significantly compared to that in conservative surveillance as early as 3 months after successful, curative PTX, and remained improved for 3 years. This finding strengthens, even more, the hypothesis that PTX contributes to better QoL, suggesting that the derangement of QoL may be considered as an individual indication for surgery.

Effects of Parathyroidectomy on Quality of Life: 10 Years of Data From a Prospective Randomized Controlled Trial on Primary Hyperparathyroidism (the SIPH-Study)

Primary hyperparathyroidism (PHPT) was previously considered a disease presenting with multiorgan involvement and a wide range of symptoms. Today, the disease presents with no symptoms or mild symptomatology in most patients. Data regarding nonspecific symptoms such as pain, fatigue, memory loss, depression, and other neuropsychiatric signs have been ambiguous, and results from prospective long-term randomized control trials are lacking. The Scandinavian Investigation on Primary Hyperparathyroidism (SIPH) is a prospective randomized controlled trial (RCT) with 10-year follow up, comparing parathyroidectomy (PTX) to observation without any treatment (OBS). From 1998 to 2005, 191 patients with mild PHPT were included from Sweden, Norway, and Denmark. A total of 95 patients were randomized to PTX and 96 to OBS. The generic Short Form-36 survey (SF-36) and the Comprehensive Psychopathological Rating Scale (CPRS) were studied at baseline, 2, 5, and 10 years after randomization. After 10 years, the PTX group scored significantly better on vitality (PTX 65.1 ± 20.2 versus OBS 57.4 ± 22.7; p = .017) compared to the OBS group in SF-36. We found no differences between the groups in the physical subscales. The OBS group had no significant change in any of the SF-36 scores throughout the study. The CPRS showed an improvement of symptoms in both groups for single items and sum scores after 10 years compared to baseline. There were, however, no significant differences between the two groups in the CPRS data. The results of this large and long-term RCT indicate improvement in some of the mental domains of SF-36 following PTX. However, the treatment effects between the groups were subtle with uncertain clinical significance. The observation group had stable SF-36 values and improvement in CPRS symptom-scores. Thus, in considering only quality of life (QoL) and in the absence of declines in renal and skeletal parameters, it may be safe to observe patients with mild PHPT for a decade. © 2020 American Society for Bone and Mineral Research (ASBMR).

Quality of Life in Patients With Hypoparathyroidism After Treatment for Thyroid Cancer

PURPOSE

Surgical complications such as hypoparathyroidism (HPT) or vocal cord palsy are seldom assessed when the quality of life (QOL) in thyroid cancer patients is investigated. The aim of this study was to measure the QOL difference in thyroid cancer survivors with and without HPT.

METHODS

Participants for this analysis were enrolled in 13 countries from a study that pilot-tested a thyroid cancer-specific QOL instrument. They were included if they had been diagnosed with thyroid cancer at least 9 months previously. QOL was measured using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core (EORTC QLQ-C30) and some items on HPT symptoms (eg, tingling in fingers or toes). HPT status and other clinical data were extracted from the patients' medical charts. Comparisons of QOL domains between patients with and without HPT were performed using Mann-Whitney U test. The occurrence of HPT-related symptoms was compared using chi-square tests. Multiple ordinal regression analysis was performed to evaluate factors that might affect QOL.

RESULTS

Eighty-nine patients participated in this study, 17 of whom were considered to have HPT. Patients in the HPT group reported significantly reduced QOL in 9 of the 15 scales of the EORTC QLQ-C30 compared to patients without HPT. Regression analysis showed that HPT was independently negatively associated with various scales of the QLQ-C30. Both groups showed a high prevalence of typical HPT symptoms.

CONCLUSION

Thyroid cancer patients with HPT report significantly impaired QOL compared to thyroid cancer survivors without HPT. The assessment of HPT should be considered when measuring QOL in thyroid cancer patients.

Recent advances in understanding and managing hypoparathyroidism

Hypoparathyroidism is a rare endocrine disorder which leads to hypocalcemia, hypercalciuria, and hyperphosphatemia. Complications include nephrocalcinosis with renal dysfunction, reduced quality of life, and abnormal skeletal properties. Conventional therapy with calcium and vitamin D analogs addresses hypocalcemia but has important limitations. Parathyroid hormone (PTH) therapy is a fundamental advance, although the effects of PTH on long-term complications require additional testing. Continuous PTH therapy is likely to be particularly advantageous for addressing renal, quality of life, and skeletal complications. Overall, much progress has been made, yet more information is needed to improve our understanding and management of hypoparathyroidism.

Secretion and Function of Pituitary Prolactin in Evolutionary Perspective

The hypothalamo-pituitary system developed in early vertebrates. Prolactin is an ancient vertebrate hormone released from the pituitary that exerts particularly diverse functions. The purpose of the review is to take a comparative approach in the description of prolactin, its secretion from pituitary lactotrophs, and hormonal functions. Since the reproductive and osmoregulatory roles of prolactin are best established in a variety of species, these functions are the primary subjects of discussion. Different types of prolactin and prolactin receptors developed during vertebrate evolution, which will be described in this review. The signal transduction of prolactin receptors is well conserved among vertebrates enabling us to describe the whole subphylum. Then, the review focuses on the regulation of prolactin release in mammals as we have the most knowledge on this class of vertebrates. Prolactin secretion in response to different reproductive stimuli, such as estrogen-induced release, mating, pregnancy and suckling is detailed. Reproduction in birds is different from that in mammals in several aspects. Prolactin is released during incubation in avian species whose regulation and functional significance are discussed. Little information is available on prolactin in reptiles and amphibians; therefore, they are mentioned only in specific cases to explain certain evolutionary aspects. In turn, the osmoregulatory function of prolactin is well established in fish. The different types of pituitary prolactin in fish play particularly important roles in the adaptation of eutherian species to fresh water environments. To achieve this function, prolactin is released from lactotrophs in hyposmolarity, as they are directly osmosensitive in fish. In turn, the released prolactin acts on branchial epithelia, especially ionocytes of the gill to retain salt and excrete water. This review will highlight the points where comparative data give new ideas or suggest new approaches for investigation in other taxa.

Quality of life of patients more than 1 year after surgery for thyroid cancer

PURPOSE

Patients with thyroid cancer are often assumed to have no quality of life (QOL) impairments after treatment because of thyroid cancer's good prognosis. However, the QOL implications of surgical complications and the necessity to take lifelong medication are seldom assessed.

METHODS

Patients who had surgery due to thyroid cancer at the University Medical Center Mainz between 2010 and 2015 and who had calcium or parathyroid hormone levels below the reference values immediately following surgery were eligible for this study. QOL was assessed using the EORTC QLQ-C30 and the thyroid cancer module EORTC QLQ-THY34. Multiple logistic regression was used to determine factors associated with a worse QOL compared with a general population.

RESULTS

A total of 75 (56%) of 134 eligible patients participated in the study. Patients with persistent/prolonged calcium or vitamin D intake reported worse QOL in the domains of global health, physical functioning, role functioning, emotional functioning, and insomnia than patients without current intake. Current calcium and vitamin D intake, higher education, living with a partner, and age had an effect on the odds of having worse QOL than the age- and sex-adjusted general population.

CONCLUSION

Prolonged calcium and/or vitamin D intake are negatively associated with certain domains of QOL in thyroid cancer patients who are at least 1 year post surgery. Assessment of calcium and vitamin D and diagnosis of hypoparathyroidism are therefore important for the follow-up of thyroid cancer survivors since it may affect their QOL.

The effects of patient and disease-related factors on the quality of life in patients with hypoparathyroidism

This study aims to evaluate factors affecting the quality of life (QOL) of hypoparathyroidism. While QOL is reduced in post-surgical and non-surgical groups, mental health seems to be less affected in non-surgical patients. Having an additional disease affects QOL negatively but having thyroid cancer may not change the QOL results.

PURPOSE

Hypoparathyroidism (HypoPT) is an orphan disease, which causes physical, emotional, and cognitive problems. We aimed to estimate the factors affecting the quality of life (QOL) of HypoPT patients.

METHODS

Basal characteristics, treatments, and laboratory results of the participants were recorded. QOL of the patients and controls were evaluated via the Short Form-36 (SF-36) survey.

RESULTS

One hundred sixty HypoPT patients were compared with 148 controls. Patients had lower scores in all SF-36 domains than controls. Non-surgical patients had better scores in vitality and mental health compared with post-surgical ones. Males had higher scores in mental and physical health domains than females. Non-surgical patients had higher scores in mental health compared with post-surgical ones when calcium levels were between 8 and 8.9 mg/dL. When we compared the patients with the pathological results, QOL scores of post-surgical patients with thyroid cancer were not different from the patients with thyroid nodular hyperplasia. HypoPT patients having an additional disease presented lower scores in physical functions and general health. Disease duration was found out positively correlated with vitality in non-surgical patients.

CONCLUSION

While QOL is reduced in both post-surgical and non-surgical HypoPT groups, mental health seems to be less affected in non-surgical patients. Non-surgical patients might be tolerating hypocalcemia symptoms, lower calcium levels, and longer disease duration better than post-surgical ones. Having an additional disease affects the QOL negatively but having thyroid cancer may not change the QOL results of post-surgical patients.

Burden of illness in not adequately controlled chronic hypoparathyroidism: Findings from a 13-country patient and caregiver survey

OBJECTIVE

To address knowledge gaps regarding burdens associated with not adequately controlled chronic hypoparathyroidism.

DESIGN

Global patient and caregiver survey.

STUDY POPULATIONS

Patients with chronic hypoparathyroidism not adequately controlled on conventional therapy and their caregivers.

MEASUREMENTS

Health-related quality of life (HRQoL) and health status were evaluated using the 36-item Short Form version 2 (SF-36 v2.0) and Five-Level EuroQoL 5 Dimensions (EQ-5D-5L) instruments, respectively. Hypoparathyroidism-associated symptoms were assessed by a disease-specific Hypoparathyroidism Symptom Diary and caregiver burden via the Modified Caregiver Strain Index (MCSI).

RESULTS

Data were obtained from 398 patients and 207 caregivers. Patients' self-rated hypoparathyroidism-related symptom severity was none (3%), mild (32%), moderate (53%) or severe (12%). Per the Hypoparathyroidism Symptom Diary, patients reported moderate, severe or very severe symptoms of physical fatigue (73%), muscle cramps (55%), heaviness in limbs (55%) and tingling (51%) over a 7-day recall period. Impacts (rated 'somewhat' or 'very much') were reported by 84% of patients for ability to exercise, 78% for sleep, 75% for ability to work and 63% for family relationships. Inverse relationships were observed between patient self-rated overall symptom severity and HRQoL and health status assessment scores-the greater the symptom severity, the lower the SF-36 and EQ-5D-5L scores. Caregiver burden increased with patient self-rated symptom severity: none, 1.7 MCSI; mild, 5.4 MCSI; moderate, 9.5 MCSI; and severe, 12.5 MCSI.

CONCLUSION

Patients with not adequately controlled hypoparathyroidism reported substantial symptoms and impacts. Greater patient symptom severity was associated with decreased patient HRQoL and health status assessments and increased caregiver burden.

Mental Effects of Excess Parathyroid Hormone in Hemodialysis Patients: A Possible Role for Parathyroid 2 Hormone Receptor?

Depression as measured by the kidney disease quality of life (KDQOL) form is known to be an independent risk factor for mortality dialysis patients. Excess parathyroid hormone (PTH) has long been associated with neuropsychiatric disturbances. Those psychiatric complications are currently attributed to hypercalcemia with very little evidence; however, with the discovery of the parathyroid hormone 2 receptor (PTH2R) in the brain which can be activated by PTH, PTH2R might indicate a direct effect of PTH. As secondary and tertiary hyperparathyroidism is common in dialysis patients where the serum calcium is low or normal, we chose to investigate a possible relationship between PTH levels and depression in dialysis patients. This was a matched pair observational study with 10 patients with intact PTH values above 1000 pg/mL who were matched with 10 patients who had PTH values less than 400 pg/mL for the presence of diabetes, years on dialysis, duration of dialysis time, Kt/V, hemoglobin, and 25 OH vitamin D levels, as well as intravenous iron and erythropoietin administration. The Kidney Disease Quality of Life questionnaire (KDQOL-36) scores and patient Health Questionnaire scores were analyzed during that time. All variables underwent tests for normality and matched pair t-test. All subscales of the KDQOL-36 were worse in the high PTH group with the effect on daily life reaching P = 0.01 and the burden of disease and symptoms both reaching P = 0.02. PTH and PTH2R may be appropriate targets for investigations to improve the quality of life in hemodialysis patients.

Quality of Life in Hypoparathyroidism Improves With rhPTH(1-84) Throughout 8 Years of Therapy

CONTEXT

Calcium and vitamin D treatment does not improve reduced quality of life (QOL) in hypoparathyroidism. Recombinant human (rh) PTH(1-84) therapy improves QOL metrics for up to 5 years. Data on QOL beyond this time point are not available.

OBJECTIVES

To evaluate the effects of 8 years of rhPTH(1-84) therapy on QOL and factors associated with long-term benefit.

DESIGN

Prospective, open-label trial.

SETTING

Referral center.

PATIENTS

Twenty patients with hypoparathyoidism.

MAIN OUTCOME MEASURES

RAND 36-Item Short Form Health Survey (SF-36).

RESULTS

rhPTH therapy led to substantial improvement in five of the eight SF-36 domains [vitality, social functioning (SF), mental health (MH), bodily pain (BP) and general health] and three of these domains (SF, MH, BP) were no longer lower than the reference population. The improvement in the mental component summary (MCS) score was sustained through 8 years, while the physical component summary (PCS) score improved through 6 years. A lower baseline QOL score was associated with greater improvement. A threshold value <238 (MCS) and <245 (PCS) predicted long-term improvement in 90% and 100% of the cohort, respectively. In patients whose calcium supplementation was reduced, MCS and PCS scores improved more than those whose supplementation did not decline to the same extent. Improvement in PCS was greater in patients whose calcitriol dosage was reduced and duration of disease was shorter.

CONCLUSIONS

rhPTH(1-84) improves long-term well-being in hypoparathyroidism. The improvements are most prominent in those with impaired SF-36 at baseline and those whose requirements for conventional therapy decreased substantially.

Thalamic integration of social stimuli regulating parental behavior and the oxytocin system

Critically important components of the maternal neural circuit in the preoptic area robustly activated by suckling were recently identified. In turn, suckling also contributes to hormonal adaptations to motherhood, which includes oxytocin release and consequent milk ejection. Other reproductive or social stimuli can also trigger the release of oxytocin centrally, influencing parental or social behaviors. However, the neuronal pathways that transfer suckling and other somatosensory stimuli to the preoptic area and oxytocin neurons have been poorly characterized. Recently, a relay center of suckling was determined and characterized in the posterior intralaminar complex of the thalamus (PIL). Its neurons containing tuberoinfundibular peptide 39 project to both the preoptic area and oxytocin neurons in the hypothalamus. The present review argues that the PIL is a major relay nucleus conveying somatosensory information supporting maternal behavior and oxytocin release in mothers, and may be involved more generally in social cue evoked oxytocin release, too.

Self-report of psychological symptoms in hypoparathyroidism patients on conventional therapy

OBJECTIVE

Hypoparathyroidism is characterized by parathyroid hormone deficiency and hypocalcemia. It has been demonstrated that these patients may also present psychiatric symptoms and decrease of quality of life. The aims of this study were to evaluate the presence of psychopathological symptoms in a cohort of patients with hypoparathyroidism and compare to a control group.

SUBJECTS AND METHODS

Patients were submitted to a cross-sectional Symptom Checklist-90-R (SCL-90-R) questionnaire that evaluates psychopathological symptoms by means of the Global Severity Index (GSI), Positive Symptoms Total (PST) and Positive Symptom Distress Index (PSDI). A score based in the positive symptoms was calculated (T-score). The test group was composed of patients with hypoparathyroidism, and control by thyroidectomized patients without hypoparathyroidism. A correlation between the presence of psychological symptoms and clinical features was analyzed.

RESULTS

The study included 57 patients with a mean age of 51.1 ± 16.4 years; 20 as a control and 37, test group. There were no differences between groups regarding gender, mean age and age at diagnose. Hypoparathyroidism patients presented higher GSI index than the control group (p = 0.038). Mean T-score of the test group was as elevated as 58.2 ± 5.3 (reference range < 55). No correlation of the number of psychological symptoms to clinical and laboratorial parameters was observed.

CONCLUSION

Patients with hypoparathyroidism attending our outpatient clinics presented an increase in the number of self-report of psychological symptoms when compared with a control group. However, no correlation with hypocalcemia and clinical parameters was observed. Future studies are necessary to evaluated if the absence of PTH play a role on it.

Quality of life in patients with hypoparathyroidism receiving standard treatment: a systematic review

PURPOSE

Hypoparathyroidism is a rare endocrine disorder for which replacement therapy of the missing parathyroid hormone is not the standard therapeutic option. Current standard treatment consists of calcium and vitamin D supplementation. The intake of calcium and vitamin D supplementation can lead to complications and therefore might negatively influence patients' quality of life.

METHODS

A systematic literature review was performed to assess the current knowledge on the influence of hypoparathyroidism on patients' quality of life. The literature search was conducted in PubMed and Web of Science; all relevant literature published by August 24, 2016, was included.

RESULTS

In total 372 records were found. After title and abstract screening, 14 studies remained for a full-text screening. The full-text screening resulted in five studies which were included into the systematic review. Comparing the results with a norm-based reference population, three studies reported lower SF-36 scores for hypoparathyroidism patients. Two studies showed a reduced quality of life in hypoparathyroidism patients when their results were compared to control populations.

CONCLUSION

Most hypoparathyroidism patients receiving standard treatment show stable calcium and vitamin D levels. However, hypoparathyroidism patients still report reduced quality of life and experience physical, mental, and emotional symptoms. Therefore, it is assumed that the lack of parathyroid hormone directly influences the patients' quality of life. This review indicates that patients with hypoparathyroidism have a reduced quality of life in comparison to norm-based populations or matched controls. Further studies are required to quantify the effect of hypoparathyroidism on patients' quality of life using disease-specific questionnaires and controlling for the co-morbidities and etiologies of the patients.

PTH(1-84) is associated with improved quality of life in hypoparathyroidism through 5 years of therapy

CONTEXT

In hypoparathyroidism, quality of life (QOL) is compromised as compared to normal subjects. We previously reported our results showing an association with recombinant human PTH(1-84) therapy in hypoparathyroidism and improvement in QOL measures for 1 year.

OBJECTIVE

We tested the hypothesis that PTH(1-84) therapy in hypoparathyroidism through 5 years would be associated with continued improvement in QOL measures.

DESIGN

Sixty-nine hypoparathyroid subjects received open-label PTH(1-84). Before and during therapy, subjects completed the RAND 36-Item Short Form (SF-36) Health Survey, a measure of health-related QOL covering eight domains of physical and mental health.

RESULTS

At baseline, subjects scored significantly lower than the normative reference range in all 8 domains (T-scores -1.4 to -0.9; P < .001 for all). With PTH therapy, intention-to-treat analysis showed significant improvement in the overall score at 2 months that persisted through 5 years (386 ± 19 to 482 ± 25; P < .0001). The mental component summary score improved at 2 months and was sustained through 5 years (199 ± 11 to 246 ± 14; P = .001), as did all four individual mental health domains and T-scores (vitality, social functioning, role emotional, mental health). The physical component summary score improved at 2 months and was sustained through 5 years (187 ± 10 to 237 ± 13; P < .0001), as did 3 physical health domains and T-scores (physical functioning, role physical, general health).

CONCLUSIONS

PTH(1-84) therapy is not only associated with improvement in biochemical and skeletal indices, previously well-documented, but also in mental and physical health as determined by the SF-36 metric.

Therapy of hypoparathyroidism by replacement with parathyroid hormone

Hypoparathyroidism (HypoPT) is a state of hypocalcemia due to inappropriate low levels of parathyroid hormone (PTH). HypoPT is normally treated by calcium supplements and activated vitamin D analogues. Although plasma calcium is normalized in response to conventional therapy, quality of life (QoL) seems impaired and patients are at increased risk of renal complications. A number of studies have suggested subcutaneous injections with PTH as an alternative therapy. By replacement with the missing hormone, urinary calcium may be lowered and QoL may improve. PTH replacement therapy (PTH-RT) possesses, nevertheless, a number of challenges. If PTH is injected only once a day, fluctuations in calcium levels may occur resulting in hypercalcemia in the hours following an injection. Twice-a-day injections seem to cause less fluctuation in plasma calcium but do stimulate bone turnover to above normal. Most recently, continuous delivery of PTH by pump has appeared as a feasible alternative to injections. Plasma calcium levels do not fluctuate, urinary calcium is lowered, and bone turnover is only stimulated modestly (into the normal range). Further studies are needed to assess the long-term effects. If beneficial, it seems likely that standard treatment of HypoPT in the future will change into replacement therapy with the missing hormone.

Thalamic neuropeptide mediating the effects of nursing on lactation and maternal motivation

Nursing has important physiological and psychological consequences on mothers during the postpartum period. Tuberoinfundibular peptide of 39 residues (TIP39) may contribute to its effects on prolactin release and maternal motivation. Since TIP39-containing fibers and the receptor for TIP39, the parathyroid hormone 2 receptor (PTH2 receptor) are abundant in the arcuate nucleus and the medial preoptic area, we antagonized TIP39 action locally to reveal its actions. Mediobasal hypothalamic injection of a virus encoding an antagonist of the PTH2 receptor markedly decreased basal serum prolactin levels and the suckling-induced prolactin release. In contrast, injecting this virus into the preoptic area had no effect on prolactin levels, but did dampen maternal motivation, judged by reduced time in a pup-associated cage during a place preference test. In support of an effect of TIP39 on maternal motivation, we observed that TIP39 containing fibers and terminals had the same distribution within the preoptic area as neurons expressing Fos in response to suckling. Furthermore, TIP39 terminals closely apposed the plasma membrane of 82% of Fos-ir neurons. Retrograde tracer injected into the arcuate nucleus and the medial preoptic area labeled TIP39 neurons in the posterior intralaminar complex of the thalamus (PIL), indicating that these cells but not other groups of TIP39 neurons project to these hypothalamic regions. We also found that TIP39 mRNA levels in the PIL markedly increased around parturition and remained elevated throughout the lactation period, demonstrating the availability of the peptide in postpartum mothers. Furthermore, suckling, but not pup exposure without physical contact, increased Fos expression by PIL TIP39 neurons. These results indicate that suckling activates TIP39 neurons in the PIL that affect prolactin release and maternal motivation via projections to the arcuate nucleus and the preoptic area, respectively.

Neuropsychological dysfunction in idiopathic hypoparathyroidism and its relationship with intracranial calcification and serum total calcium

BACKGROUND

There is limited information on neuropsychological and neurological dysfunctions in patients with idiopathic hypoparathyroidism (IH).

OBJECTIVE

To assess neuropsychological and neurological dysfunctions in IH and its associated factors in a cross-sectional design.

METHOD

Neuropsychological functions were assessed in 62 patients with IH and 70 controls using a battery of cognitive tests. Neurological assessment included extrapyramidal and cerebellar signs. Assessment of intracranial calcification and volume of basal ganglia calcification (BGC) were made on computed tomography and of calcium control by averaging serum total calcium values available during the follow-up.

RESULTS

A significantly higher proportion of patients with IH showed neuropsychological dysfunctions than controls (32.3 (95% CI: 20.9-45.3) vs 5.7% (95% CI: 1.6-14.0), P<0.001). Neurological signs were present in 35.5% patients (extrapyramidal: 16.1%; cerebellar: 20.9%). Volume of BGC and number of sites with intracranial calcifications including cerebellum/dentate were comparable in patients with and without neuropsychological, extrapyramidal or cerebellar dysfunctions. Cognitive dysfunction score was lower by 1.7 points in males than in females (P=0.02) and increased by 0.21 and 5.5 for each year increase in the duration of illness (P=0.001) and one unit increase in serum calcium-phosphorus product (P=0.01) respectively. The scores improved by 0.27 for every mg% increase in serum calcium (P=0.001).

CONCLUSION

Neuropsychological dysfunctions are present in up to one-third of patients with IH and correlate with duration of illness, female gender, serum calcium and calcium-phosphorus product during follow-up but not with intracranial calcification. These dysfunctions may affect their daily functions, safety and drug compliance.

The effect of PTH(1-84) on quality of life in hypoparathyroidism

CONTEXT

Complaints from hypoparathyroid patients often reflect a reduction in quality of life (QOL), yet few data exist characterizing these complaints or the potential effects of PTH therapy to ameliorate them.

OBJECTIVE

We tested the hypothesis that PTH(1-84) therapy improves QOL in hypoparathyroidism.

DESIGN

Fifty-four hypoparathyroid subjects received open-label recombinant human PTH(1-84). Before and during PTH(1-84), subjects completed the RAND 36-Item Health Survey, a measure of health-related QOL covering 8 domains of physical and mental health.

RESULTS

At baseline, subjects scored significantly lower than the normative reference range in all 8 domains (T-scores -1.35 to -0.78; P < 0.001 for all). With PTH(1-84), the total score improved as early as month 1 and remained higher through 1 year (400 ± 200 to 478 ± 230; P = 0.001). The overall mental component summary score improved (204 ± 110 to 247 ± 130; P = 0.001), as did 3 mental health domains (vitality, social functioning, and mental health), all within 1 month (T-scores improving from -1.3 to -0.7, -1.0 to -0.6, and -0.9 to -0.3, respectively; P < 0.05 for all). The overall physical component summary score also increased by 1 month and remained higher at 1 year (196 ± 110 to 231 ± 130; P = 0.003) as did 2 physical health domains (physical functioning and general health: T-scores improving from -0.8 to -0.4, -1.2 to -0.8, respectively; P < 0.01 for both).

CONCLUSIONS

These data suggest that hypoparathyroidism is associated with compromised QOL. Along with improved biochemical control, these results indicate that PTH(1-84) treatment of hypoparathyroidism improves physical and mental functioning.

Severe hypercalcemic hyperparathyroidism developing in a patient with hyperaldosteronism and renal resistance to parathyroid hormone

We evaluated an African American woman referred in 1986 at age 33 years because of renal potassium and calcium wasting and chronic hip pain. She presented normotensive, hypokalemic, hypocalcemic, normophosphatemic, and hypercalciuric. Marked hyperparathyroidism was evident. Urinary cyclic adenosine monophosphate (cAMP) excretion did not increase in response to parathyroid hormone (PTH) infusion, indicating renal resistance to PTH. X-rays and bone biopsy revealed severe osteitis fibrosa cystica, confirming skeletal responsiveness to PTH. Renal potassium wasting, suppressed plasma renin activity, and elevated plasma and urinary aldosterone levels accompanied her hypokalemia, suggesting primary hyperaldosteronism. Hypokalemia resolved with spironolactone and, when combined with dietary sodium restriction, urinary calcium excretion fell and hypocalcemia improved, in accord with the known positive association between sodium intake and calcium excretion. Calcitriol and oral calcium supplements did not suppress the chronic hyperparathyroidism nor did they reduce aldosterone levels. Over time, hyperparathyroid bone disease progressed with pathologic fractures and persistent pain. In 2004, PTH levels increased further in association with worsening chronic kidney disease. Eventually hypercalcemia and hypertension developed. Localizing studies in 2005 suggested a left inferior parathyroid tumor. After having consistently declined, the patient finally agreed to neck exploration in January 2009. Four hyperplastic parathyroid glands were removed, followed immediately by severe hypocalcemia, attributed to "hungry bone syndrome" and hypoparathyroidism, which required prolonged hospitalization, calcium infusions, and oral calcitriol. Although her bone pain resolved, hyperaldosteronism persisted.

Regulation of hypothalamic signaling by tuberoinfundibular peptide of 39 residues is critical for the response to cold: a novel peptidergic mechanism of thermoregulation

Euthermia is critical for mammalian homeostasis. Circuits within the preoptic hypothalamus regulate temperature, with fine control exerted via descending GABAergic inhibition of presympathetic motor neurons that control brown adipose tissue (BAT) thermogenesis and cutaneous vascular tone. The thermoregulatory role of hypothalamic excitatory neurons is less clear. Here we report peptidergic regulation of preoptic glutamatergic neurons that contributes to temperature regulation. Tuberoinfundibular peptide of 39 residues (TIP39) is a ligand for the parathyroid hormone 2 receptor (PTH2R). Both peptide and receptor are abundant in the preoptic hypothalamus. Based on PTH2R and vesicular glutamate transporter 2 (VGlut2) immunolabeling in animals with retrograde tracer injection, PTH2R-containing glutamatergic fibers are presynaptic to neurons projecting from the median preoptic nucleus (MnPO) to the dorsomedial hypothalamus. Transneuronal retrograde pathway tracing with pseudorabies virus revealed connectivity between MnPO VGlut2 and PTH2R neurons and BAT. MnPO injection of TIP39 increased body temperature by 2°C for several hours. Mice lacking TIP39 signaling, either because of PTH2R-null mutation or brain delivery of a PTH2R antagonist had impaired heat production upon cold exposure, but no change in basal temperature and no impairment in response to a hot environment. Thus, TIP39 appears to act on PTH2Rs present on MnPO glutamatergic terminals to regulate their activation of projection neurons and subsequent sympathetic BAT activation. This excitatory mechanism of heat production appears to be activated on demand, during cold exposure, and parallels the tonic inhibitory GABAergic control of body temperature.

Adrenergic and cardiac dysfunction in primary hyperparathyroidism

OBJECTIVE

Primary hyperparathyroidism (PHPT) is associated with cardiovascular morbidity and premature death, but the underlying mechanisms are incompletely understood. The aim of this study was to investigate whether adrenergic dysfunction may be a contributing factor.

PATIENTS AND METHODS

Forty-nine patients with mild PHPT (serum calcium 2·7 ± 0·1 mM) and 48 control subjects, matched for age and sex, were examined; patients within 1 month before parathyroidectomy (PTX) and 6 months postoperatively; control subjects at inclusion. Heart rate variability (HRV) was analysed in 24-h electrocardiograms, and plasma concentrations of epinephrine and norepinephrine were measured at rest and immediately after standardized physical tests.

RESULTS

At baseline, the patients showed, compared to the controls, reduced stress-related increase of circulating epinephrine (P < 0·05) and norepinephrine (P < 0·05). No significant change was observed 6 months after PTX. At baseline, there were no significant differences between patients and controls in HRV or heart rate, but 6 months after curative PTX, the patients showed significantly reduced HRV in both frequency and time domain, and their maximum and average heart rate had decreased (P = 0·011 and P = 0·018, respectively). The patients with the highest preoperative levels of circulating parathyroid hormone showed the greatest changes in heart rate and HRV postoperatively.

CONCLUSIONS

This study demonstrates a previously unknown impairment of catecholamine response to physical stress in PHPT along with changes of HRV, also indicating adrenergic dysfunction. These factors should be considered in the ongoing controversy regarding the management of patients with mild 'asymptomatic' PHPT.

The neuroendocrine functions of the parathyroid hormone 2 receptor

The G-protein coupled parathyroid hormone 2 receptor (PTH2R) is concentrated in endocrine and limbic regions in the forebrain. Its endogenous ligand, tuberoinfundibular peptide of 39 residues (TIP39), is synthesized in only two brain regions, within the posterior thalamus and the lateral pons. TIP39-expressing neurons have a widespread projection pattern, which matches the PTH2R distribution in the brain. Neuroendocrine centers including the preoptic area, the periventricular, paraventricular, and arcuate nuclei contain the highest density of PTH2R-positive networks. The administration of TIP39 and an antagonist of the PTH2R as well as the investigation of mice that lack functional TIP39 and PTH2R revealed the involvement of the PTH2R in a variety of neural and neuroendocrine functions. TIP39 acting via the PTH2R modulates several aspects of the stress response. It evokes corticosterone release by activating corticotropin-releasing hormone-containing neurons in the hypothalamic paraventricular nucleus. Block of TIP39 signaling elevates the anxiety state of animals and their fear response, and increases stress-induced analgesia. TIP39 has also been suggested to affect the release of additional pituitary hormones including arginine-vasopressin and growth hormone. A role of the TIP39-PTH2R system in thermoregulation was also identified. TIP39 may play a role in maintaining body temperature in a cold environment via descending excitatory pathways from the preoptic area. Anatomical and functional studies also implicated the TIP39-PTH2R system in nociceptive information processing. Finally, TIP39 induced in postpartum dams may play a role in the release of prolactin during lactation. Potential mechanisms leading to the activation of TIP39 neurons and how they influence the neuroendocrine system are also described. The unique TIP39-PTH2R neuromodulator system provides the possibility for developing drugs with a novel mechanism of action to control neuroendocrine disorders.

Evolution of the vertebrate pth2 (tip39) gene family and the regulation of PTH type 2 receptor (pth2r) and its endogenous ligand pth2 by hedgehog signaling in zebrafish development

In mammals, parathyroid hormone (PTH), secreted by parathyroid glands, increases calcium levels in the blood from reservoirs in bone. While mammals have two PTH receptor genes, PTH1R and PTH2R, zebrafish has three receptors, pth1r, pth2r, and pth3r. PTH can activate all three zebrafish Pthrs while PTH2 (alias tuberoinfundibular peptide 39, TIP39) preferentially activates zebrafish and mammalian PTH2Rs. We know little about the roles of the PTH2/PTH2R system in the development of any animal. To determine the roles of PTH2 and PTH2R during vertebrate development, we evaluated their expression patterns in developing zebrafish, observed their phylogenetic and conserved synteny relationships with humans, and described the genomic organization of pth2, pth2r, and pth2r splice variants. Expression studies showed that pth2 is expressed in cells adjacent to the ventral part of the posterior tuberculum in the diencephalon, whereas pth2r is robustly expressed throughout the central nervous system. Otic vesicles express both pth2 and pth2r, but heart expresses only pth2. Analysis of mutants showed that hedgehog (Hh) signaling regulates the expression of pth2 transcripts more than that of nearby gnrh2-expressing cells. Genomic analysis showed that a lizard, chicken, and zebra finch lack a PTH2 gene, which is associated with an inversion breakpoint. Likewise, chickens lack PTH2R, while humans lack PTH3R, a case of reciprocally missing ohnologs (paralogs derived from a genome duplication). The considerable evolutionary conservation in genomic structure, synteny relationships, and expression of zebrafish pth2 and pth2r provides a foundation for exploring the endocrine roles of this system in developing vertebrate embryos.

Tuberoinfundibular peptide of 39 residues- immunoreactive fibers in the zona incerta and the supraoptic decussations terminate in the neuroendocrine hypothalamus

Tuberoinfundibular peptide of 39 residues (TIP39) is expressed by neurons in the subparafascicular area, the posterior intralaminar complex of the thalamus and the pontine medial paralemniscal nucleus. TIP39-positive fibers from these areas do not form individual bundles or fascicles, they join other pathways to reach their innervated brain areas. Fibers arise from TIP39 perikarya located in the subparafascicular area and the posterior intralaminar complex of the thalamus could be followed to the hypothalamus. After uni- and bilateral posterolateral surgical deafferentations of the hypothalamus, accumulation of TIP39 immunoreactivity was observed in the fibers caudal to the knife cut, while it disappeared completely rostral to the transection. In serial sections of the forebrain, we could follow TIP39-ir fibers coursing within the zona incerta and the supraoptic decussations. TIP39-positive fibers that join the incerto-hypothalamic pathway reach the medio-dorsal part of the hypothalamus and form moderate to high density networks in the dorsomedial and paraventricular nuclei. The other set of TIP39-positive axons from the subthalamic area join the fibers of the supraoptic decussations and run in an antero-medial direction through the most ventral portion of the hypothalamus up to the retrochiasmatic area, where they crossover. A certain portion of these TIP39-positive fibers terminates in the territories of the arcuate and the medial preoptic nuclei, as well as in the retrochiasmatic area.

Tuberoinfundibular peptide of 39 residues (TIP39) signaling modulates acute and tonic nociception

Tuberoinfundibular peptide of 39 residues (TIP39) synthesizing neurons at the caudal border of the thalamus and in the lateral pons project to areas rich in its receptor, the parathyroid hormone 2 receptor (PTH2R). These areas include many involved in processing nociceptive information. Here we examined the potential role of TIP39 signaling in nociception using a PTH2R antagonist (HYWH) and mice with deletion of TIP39's coding sequence or PTH2R null mutation. Intracerebroventricular (icv) infusion of HYWH significantly inhibited nociceptive responses in tail-flick and hot-plate tests and attenuated the nociceptive response to hindpaw formalin injection. TIP39-KO and PTH2R-KO had increased response latency in the 55°C hot-plate test and reduced responses in the hindpaw formalin test. The tail-flick test was not affected in either KO line. Thermal hypoalgesia in KO mice was dose-dependently reversed by systemic administration of the cannabinoid receptor 1 (CB1) antagonist rimonabant, which did not affect nociception in wild-type (WT). Systemic administration of the cannabinoid agonist CP 55,940 did not affect nociception in KO mice at a dose effective in WT. WT mice administered HYWH icv, and both KOs, had significantly increased stress-induced analgesia (SIA). Rimonabant blocked the increased SIA in TIP39-KO, PTH2R-KO or after HYWH infusion. CB1 and FAAH mRNA were decreased and increased, respectively, in the basolateral amygdala of TIP39-KO mice. These data suggest that TIP39 signaling modulates nociception, very likely by inhibiting endocannabinoid circuitry at a supraspinal level. We infer a new central mechanism for endocannabinoid regulation, via TIP39 acting on the PTH2R in discrete brain regions.

The TIP39-PTH2 receptor system: unique peptidergic cell groups in the brainstem and their interactions with central regulatory mechanisms

Tuberoinfundibular peptide of 39 residues (TIP39) is the recently purified endogenous ligand of the previously orphan G-protein coupled parathyroid hormone 2 receptor (PTH2R). The TIP39-PTH2R system is a unique neuropeptide-receptor system whose localization and functions in the central nervous system are different from any other neuropeptides. TIP39 is expressed in two brain regions, the subparafascicular area in the posterior thalamus, and the medial paralemniscal nucleus in the lateral pons. Subparafascicular TIP39 neurons seem to divide into a medial and a lateral cell population in the periventricular gray of the thalamus, and in the posterior intralaminar complex of the thalamus, respectively. Periventricular thalamic TIP39 neurons project mostly to limbic brain regions, the posterior intralaminar thalamic TIP39 neurons to neuroendocrine brain areas, and the medial paralemniscal TIP39 neurons to auditory and other brainstem regions, and the spinal cord. The widely distributed axon terminals of TIP39 neurons have a similar distribution as the PTH2R-containing neurons, and their fibers, providing the anatomical basis of a neuromodulatory action of TIP39. Initial functional studies implicated the TIP39-PTH2R system in nociceptive information processing in the spinal cord, in the regulation of different hypophysiotropic neurons in the hypothalamus, and in the modulation of affective behaviors. Recently developed novel experimental tools including mice with targeted mutations of the TIP39-PTH2R system and specific antagonists of the PTH2R will further facilitate the identification of the specific roles of TIP39 and the PTH2R.

Acoustic stress activates tuberoinfundibular peptide of 39 residues neurons in the rat brain

Strong acoustic stimulation (105 dB SPL white noise) elicited c-fos expression in neurons in several acoustic system nuclei and in stress-sensitive hypothalamic nuclei and limbic areas in rats. In the present study, using this type of loud noise for 30 min, Fos-like immunoreactivity (Fos-ir) was investigated in neurons that synthesize tuberoinfundibular peptide of 39 residues (TIP39) in the rat brain: in the subparafascicular area of the thalamus, the posterior intralaminar complex of the thalamus and the medial paralemniscal nucleus in the lateral part of the pons. By double labeling, Fos-ir was shown in nearly 80% of TIP39-positive cells in the medial paralemniscal nucleus, 43% in the posterior intralaminar complex and 18.5% in the subparafascicular area 30 min after the end of a 30-min loud noise period. In control rats, only few neurons, including 0-4% of TIP39-positive neurons showed Fos-ir. While the majority of the Fos-ir neurons were TIP39-positive in the subparafascicular area and medial paralemniscal nucleus, a fairly high number of TIP39-immunonegative, chemically uncharacterized neurons expressed c-fos in the subparafascicular area and the posterior intralaminar complex of the thalamus. These observations clearly show that some TIP39 neurons in the so-called "acoustic thalamus" and the majority of TIP39 neurons in the medial paralemniscal nucleus are sensitive to loud noise and they may participate in the central organization of responses to acoustic stress. Furthermore, the present data suggest that non-TIP39-expressing neurons may play a prevalent role in the activity of the "acoustic thalamus".