<script type="application/ld+json">
{
  "@context": "http://schema.org",
  "@type": "NewsArticle",
  "headline": "<?php echo get_post_meta($post->ID, '_aioseop_title', true); ?>",
  "image": ["<?php echo get_the_post_thumbnail( $page->ID, 'thumbnail'); ?>"],
  "datePublished": "<?php echo the_time('Y-m-d'); ?>T08:00:00+08:00",
  "description": <?php
                       $my_descr = get_post_meta($post->ID, "_aioseop_description", true);
                            if ($my_descr){
                                echo  '"'.$my_descr.'"';
                                    }
                            else echo  "Нет описания для данной страницы";?>
}
</script>